title: Neutron bomb

text: In a neutron bomb, the casing material is selected either to be transparent to neutrons or to actively enhance their production. The burst of neutrons created in the thermonuclear reaction is then free to escape the bomb, outpacing the physical explosion. By designing the thermonuclear stage of the weapon carefully, the neutron burst can be maximized while minimizing the blast itself. This makes the lethal radius of the neutron burst greater than that of the explosion itself. Since the neutrons are absorbed or decay rapidly, such a burst over an enemy column would kill the crews but leave the area able to be quickly reoccupied.


title: Neutron bomb

text: Compared to a pure fission bomb with an identical explosive yield, a neutron bomb would emit about ten times the amount of neutron radiation. In a fission bomb, at sea level, the total radiation pulse energy which is composed of both gamma rays and neutrons is approximately 5% of the entire energy released; in neutron bombs it would be closer to 40%, with the percentage increase coming from the higher production of neutrons. Furthermore, the neutrons emitted by a neutron bomb have a much higher average energy level (close to 14 MeV) than those released during a fission reaction (1–2 MeV).


title: Neutron bomb

text: Technically speaking, every low yield nuclear weapon is a radiation weapon, including non-enhanced variants. All nuclear weapons up to about 10 kilotons in yield have prompt neutron radiation as their furthest-reaching lethal component. For standard weapons above about 10 kilotons of yield, the lethal blast and thermal effects radius begins to exceed the lethal ionizing radiation radius. Enhanced radiation weapons also fall into this same yield range and simply enhance the intensity and range of the neutron dose for a given yield.


title: Neutron bomb

text: The conception of neutron bombs is generally credited to Samuel T. Cohen of the Lawrence Livermore National Laboratory, who developed the concept in 1958. Initial development was carried out as part of projects Dove and Starling, and an early device was tested underground in early 1962. Designs for a "weaponized" version were developed in 1963.


title: Neutron bomb

text: Development of two production designs for the army's MGM-52 Lance short-range missile began in July 1964, the W63 at Livermore and the W64 at Los Alamos. Both entered phase three testing in July 1964, and the W64 was cancelled in favor of the W63 in September 1964. The W63 was in turn cancelled in November 1965 in favor of the W70 (Mod 0), a conventional design. By this time, the same concepts were being used to develop warheads for the Sprint missile, an anti-ballistic missile (ABM), with Livermore designing the W65 and Los Alamos the W66. Both entered phase three testing in October 1965, but the W65 was cancelled in favor of the W66 in November 1968. Testing of the W66 was carried out in the late 1960s, and it entered production in June 1974, the first neutron bomb to do so. Approximately 120 were built, with about 70 of these being on active duty during 1975 and 1976 as part of the Safeguard Program. When that program was shut down they were placed in storage, and eventually decommissioned in the early 1980s.


title: Neutron bomb

text: Development of ER warheads for Lance continued, but in the early 1970s attention had turned to using modified versions of the W70, the W70 Mod 3. Development was subsequently postponed by President Jimmy Carter in 1978 following protests against his administration's plans to deploy neutron warheads to ground forces in Europe. On November 17, 1978, in a test the USSR detonated its first similar-type bomb. President Ronald Reagan restarted production in 1981. The Soviet Union renewed a propaganda campaign against the US's neutron bomb in 1981 following Reagan's announcement. In 1983 Reagan then announced the Strategic Defense Initiative, which surpassed neutron bomb production in ambition and vision and with that, neutron bombs quickly faded from the center of the public's attention.


title: Neutron bomb

text: Three types of enhanced radiation weapons (ERW) were deployed by the United States. The W66 warhead, for the anti-ICBM Sprint missile system, was deployed in 1975 and retired the next year, along with the missile system. The W70 Mod 3 warhead was developed for the short-range, tactical MGM-52 Lance missile, and the W79 Mod 0 was developed for nuclear artillery shells. The latter two types were retired by President George H. W. Bush in 1992, following the end of the Cold War. The last W70 Mod 3 warhead was dismantled in 1996, and the last W79 Mod 0 was dismantled by 2003, when the dismantling of all W79 variants was completed.


title: Neutron bomb

text: According to the Cox Report, as of 1999 the United States had never deployed a neutron weapon. The nature of this statement is not clear; it reads "The stolen information also includes classified design information for an enhanced radiation weapon (commonly known as the "neutron bomb"), which neither the United States, nor any other nation, has ever deployed." However, the fact that neutron bombs had been produced by the US was well known at this time and part of the public record. Cohen suggests the report is playing with the definitions; while the US bombs were never deployed "to Europe", they remained stockpiled in the US.


title: Neutron bomb

text: In addition to the two superpowers, France and China are known to have tested neutron or enhanced radiation bombs. France conducted an early test of the technology in 1967 and tested an "actual" neutron bomb in 1980. China conducted a successful test of neutron bomb principles in 1984 and a successful test of a neutron bomb in 1988. However, neither of those countries chose to deploy neutron bombs. Chinese nuclear scientists stated before the 1988 test that China had no need for neutron bombs, but it was developed to serve as a "technology reserve", in case the need arose in the future.


title: Neutron bomb

text: In May 1998, Senior Pakistani Scientist, Dr. N. M. Butt, stated that "PAEC built a sufficient number of neutron bombs—a battlefield weapon that is essentially a low yield device".


title: Neutron bomb

text: Although no country is currently known to deploy them in an offensive manner, all thermonuclear dial-a-yield warheads that have about 10 kiloton and lower as one dial option, with a considerable fraction of that yield derived from fusion reactions, can be considered able to be neutron bombs in use, if not in name. The only country definitely known to deploy dedicated (that is, not dial-a-yield) neutron warheads for any length of time is the Soviet Union/Russia, which inherited the USSR's neutron warhead equipped ABM-3 Gazelle missile program. This ABM system contains at least 68 neutron warheads with a 10 kiloton yield each and it has been in service since 1995, with inert missile testing approximately every other year since then (2014). The system is designed to destroy incoming endoatmospheric nuclear warheads aimed at Moscow and other targets and is the lower-tier/last umbrella of the A-135 anti-ballistic missile system (NATO reporting name: ABM-3).


title: Neutron bomb

text: Considerable controversy arose in the US and Western Europe following a June 1977 "Washington Post" exposé describing US government plans to equip US Armed Forces with neutron bombs. The article focused on the fact that it was the first weapon specifically intended to kill humans with radiation. Lawrence Livermore National Laboratory director Harold Brown and Soviet General Secretary Leonid Brezhnev both described neutron bombs as a "capitalist bomb", because it was designed to destroy people while preserving property.


title: Neutron bomb

text: Neutron bombs are purposely designed with explosive yields lower than other nuclear weapons. Since neutrons are scattered and absorbed by air, neutron radiation effects drop off rapidly with distance in air. As such, there is a sharper distinction, relative to thermal effects, between areas of high lethality and areas with minimal radiation doses. All high yield (more than c. 10 kiloton) nuclear bombs, such as the extreme example of a device that derived 97% of its energy from fusion, the 50 megaton Tsar Bomba, are not able to radiate sufficient neutrons beyond their lethal blast range when detonated as a surface burst or low altitude air burst and so are no longer classified as neutron bombs, thus limiting the yield of neutron bombs to a maximum of about 10 kilotons. The intense pulse of high-energy neutrons generated by a neutron bomb is the principal killing mechanism, not the fallout, heat or blast.


title: Neutron bomb

text: The inventor of the neutron bomb, Sam Cohen, criticized the description of the W70 as a neutron bomb since it could be configured to yield 100 kilotons:


title: Neutron bomb

text: Although neutron bombs are commonly believed to "leave the infrastructure intact", with current designs that have explosive yields in the low kiloton range, detonation in (or above) a built-up area would still cause a sizable degree of building destruction, through blast and heat effects out to a moderate radius, albeit considerably less destruction, than when compared to a standard nuclear bomb of the "exact" same total energy release or "yield".


title: Neutron bomb

text: The Warsaw Pact tank strength was over twice that of NATO, and Soviet deep battle doctrine was likely to be to use this numerical advantage to rapidly sweep across continental Europe if the Cold War ever turned hot. Any weapon that could break up their intended mass tank formation deployments and force them to deploy their tanks in a thinner, more easily dividable manner, would aid ground forces in the task of hunting down solitary tanks and using anti-tank missiles against them, such as the contemporary M47 Dragon and BGM-71 TOW missiles, of which NATO had hundreds of thousands.


title: Neutron bomb

text: Rather than making extensive preparations for battlefield nuclear combat in Central Europe, the Soviet military leadership believed that conventional superiority provided the Warsaw Pact with the means to approximate the effects of nuclear weapons and achieve victory in Europe without resort to those weapons.


title: Neutron bomb

text: Neutron bombs, or more precisely, enhanced [neutron] radiation weapons were also to find use as strategic anti-ballistic missile weapons, and in this role they are believed to remain in active service within Russia's Gazelle missile.


title: Neutron bomb

text: Upon detonation, a near-ground airburst of a 1 kiloton neutron bomb would produce a large blast wave and a powerful pulse of both thermal radiation and ionizing radiation in the form of fast (14.1MeV) neutrons. The thermal pulse would cause third degree burns to unprotected skin out to approximately 500 meters. The blast would create pressures of at least 4.6psi (32 kPa) out to a radius of 600 meters, which would severely damage all non-reinforced concrete structures. At the conventional effective combat range against modern main battle tanks and armored personnel carriers (<690–900m), the blast from a 1kt neutron bomb would destroy or damage to the point of nonusability almost all un-reinforced civilian buildings.


title: Neutron bomb

text: Using neutron bombs to stop an enemy armored attack by rapidly incapacitating crews with a dose of 80+ Gy of radiation would require exploding large numbers of them to blanket the enemy forces, destroying all normal civilian buildings within c.600 meters of the immediate area. Neutron activation from the explosions could make many building materials in the city radioactive, such as galvanized steel (see area denial use below).


title: Neutron bomb

text: Because liquid-filled objects like the human body are resistant to gross overpressure, the 4–5psi (28-34 kPa) blast overpressure would cause very few direct casualties at a range of c.600m. The powerful winds produced by this overpressure, however, could throw bodies into objects or throw debris at high velocity, including window glass, both with potentially lethal results. Casualties would be highly variable depending on surroundings, including potential building collapses.


title: Neutron bomb

text: The pulse of neutron radiation would cause immediate and permanent incapacitation to unprotected outdoor humans in the open out to 900 meters, with death occurring in one or two days. The median lethal dose (LD) of 6 Gray would extend to between 1350 and 1400 meters for those unprotected and outdoors, where approximately half of those exposed would die of radiation sickness after several weeks.


title: Neutron bomb

text: A human residing within, or simply shielded by, at least one concrete building with walls and ceilings thick, or alternatively of damp soil 24 inches (60 cm) thick, would receive a neutron radiation exposure reduced by a factor of 10. Even near ground zero, basement sheltering or buildings with similar radiation shielding characteristics would drastically reduce the radiation dose.


title: Neutron bomb

text: Furthermore, the neutron absorption spectrum of air is disputed by some authorities, and depends in part on absorption by hydrogen from water vapor. Thus, absorption might vary exponentially with humidity, making neutron bombs far more deadly in desert climates than in humid ones.


title: Neutron bomb

text: The questionable effectiveness of ER weapons against modern tanks is cited as one of the main reasons that these weapons are no longer fielded or stockpiled. With the increase in average tank armor thickness since the first ER weapons were fielded, it was argued in the March 13, 1986, "New Scientist" magazine that tank armor protection was approaching the level where tank crews would be almost fully protected from radiation effects. Thus, for an ER weapon to incapacitate a modern tank crew through irradiation, the weapon must be detonated at such proximity to the tank that the nuclear explosion's blast would now be equally effective at incapacitating it and its crew.


title: Neutron bomb

text: However although the author did note that effective neutron absorbers and neutron poisons such as boron carbide can be incorporated into conventional armor and strap-on neutron moderating hydrogenous material (substances containing hydrogen atoms), such as explosive reactive armor, can both increase the protection factor, the author holds that in practice combined with neutron scattering, the actual average total tank area protection factor is rarely higher than 15.5 to 35. According to the Federation of American Scientists, the neutron protection factor of a "tank" can be as low as 2, without qualifying whether the statement implies a light tank, medium tank, or main battle tank.


title: Neutron bomb

text: A composite high density concrete, or alternatively, a laminated graded-Z shield, 24 units thick of which 16 units are iron and 8 units are polyethylene containing boron (BPE), and additional mass behind it to attenuate neutron capture gamma rays, is more effective than just 24 units of pure iron or BPE alone, due to the advantages of both iron and BPE in combination. During Neutron transport Iron is effective in slowing down/scattering high-energy neutrons in the 14-MeV energy range and attenuating gamma rays, while the hydrogen in polyethylene is effective in slowing down these now slower fast neutrons in the few MeV range, and boron 10 has a high absorption cross section for thermal neutrons and a low production yield of gamma rays when it absorbs a neutron. The Soviet T-72 tank, in response to the neutron bomb threat, is cited as having fitted a boronated polyethylene liner, which has had its neutron shielding properties simulated.


title: Neutron bomb

text: However, some tank armor material contains depleted uranium (DU), common in the US's M1A1 Abrams tank, which incorporates steel-encased depleted uranium armor, a substance that will fast fission when it captures a fast, fusion-generated neutron, and thus on fissioning will produce fission neutrons and fission products embedded within the armor, products which emit among other things, penetrating gamma rays. Although the neutrons emitted by the neutron bomb may not penetrate to the tank crew in lethal quantities, the fast fission of DU within the armor could still ensure a lethal environment for the crew and maintenance personnel by fission neutron and gamma ray exposure, largely depending on the exact thickness and elemental composition of the armor—information usually hard to attain. Despite this, Ducrete—which has an elemental composition similar (but not identical) to the ceramic second generation heavy metal Chobham armor of the Abrams tank—is an effective radiation shield, to both "fission" neutrons and gamma rays due to it being a graded Z material. Uranium, being about twice as dense as lead, is thus nearly twice as effective at shielding gamma ray radiation per unit thickness.


title: Neutron bomb

text: As an anti-ballistic missile weapon, the first fielded ER warhead, the W66, was developed for the Sprint missile system as part of the Safeguard Program to protect United States cities and missile silos from incoming Soviet warheads.


title: Neutron bomb

text: A problem faced by Sprint and similar ABMs was that the blast effects of their warheads change greatly as they climb and the atmosphere thins out. At higher altitudes, starting around and above, the blast effects begin to drop off rapidly as the air density becomes very low. This can be countered by using a larger warhead, but then it becomes too powerful when used at lower altitudes. An ideal system would use a mechanism that was less sensitive to changes in air density.


title: Neutron bomb

text: Neutron-based attacks offer one solution to this problem. The burst of neutrons released by an ER weapon can induce fission in the fissile materials of primary in the target warhead. The energy released by these reactions may be enough to melt the warhead, but even at lower fission rates the "burning up" of some of the fuel in the primary can cause it to fail to explode properly, or "fizzle". Thus a small ER warhead can be effective across a wide altitude band, using blast effects at lower altitudes and the increasingly long-ranged neutrons as the engagement rises.


title: Neutron bomb

text: The use of neutron-based attacks was discussed as early as the 1950s, with the US Atomic Energy Commission mentioning weapons with a "clean, enhanced neutron output" for use as "antimissile defensive warheads." Studying, improving and defending against such attacks was a major area of research during the 1950s and 60s. A particular example of this is the US Polaris A-3 missile, which delivered three warheads travelling on roughly the same trajectory, and thus with a short distance between them. A single ABM could conceivably destroy all three through neutron flux. Developing warheads that were less sensitive to these attacks was also a major area of research in the US and UK during the 1960s.


title: Neutron bomb

text: Some sources claim that the neutron flux attack was also the main design goal of the various nuclear-tipped anti-aircraft weapons like the AIM-26 Falcon and CIM-10 Bomarc. One F-102 pilot noted:


title: Neutron bomb

text: It has also been suggested that neutron flux's effects on the warhead electronics are another attack vector for ER warheads in the ABM role. Ionization greater than 50 Gray in silicon chips delivered over seconds to minutes will degrade the function of semiconductors for long periods. However, while such attacks might be useful against guidance systems which used relatively advanced electronics, in the ABM role these components have long ago separated from the warheads by the time they come within range of the interceptors. The electronics in the warheads themselves tend to be very simple, and hardening them was one of the many issues studied in the 1960s.


title: Neutron bomb

text: Lithium-6 hydride (Li6H) is cited as being used as a countermeasure to reduce the vulnerability and "harden" nuclear warheads from the effects of externally generated neutrons. Radiation hardening of the warhead's electronic components as a countermeasure to high altitude neutron warheads somewhat reduces the range that a neutron warhead could successfully cause an unrecoverable glitch by the "transient radiation effects on electronics" (TREE) effects.


title: Neutron bomb

text: At very high altitudes, at the edge of the atmosphere and above it, another effect comes into play. At lower altitudes, the x-rays generated by the bomb are absorbed by the air and have mean free paths on the order of meters. But as the air thins out, the x-rays can travel further, eventually outpacing the area of effect of the neutrons. In exoatmospheric explosions, this can be on the order of in radius. In this sort of attack, it is the x-rays promptly delivering energy on the warhead surface that is the active mechanism; the rapid ablation (or "blow off") of the surface creates shock waves that can break up the warhead.


title: Neutron bomb

text: In November 2012 British Labour peer Lord Gilbert suggested that multiple enhanced radiation reduced blast (ERRB) warheads could be detonated in the mountain region of the Afghanistan-Pakistan border to prevent infiltration. He proposed to warn the inhabitants to evacuate, then irradiate the area, making it unusable and impassable. Used in this manner, the neutron bomb(s), regardless of burst height, would release neutron activated casing materials used in the bomb, and depending on burst height, create radioactive soil activation products.


title: Neutron bomb

text: In much the same fashion as the area denial effect resulting from fission product (the substances that make up most fallout) contamination in an area following a conventional surface burst nuclear explosion, as considered in the Korean War by Douglas MacArthur, it would thus be a form of radiological warfare—with the difference that neutron bombs produce half, or less, of the quantity of fission products relative to the same-yield pure fission bomb. Radiological warfare with neutron bombs that rely on fission primaries would thus still produce fission fallout, albeit a comparatively "cleaner" and shorter lasting version of it in the area than if air bursts were used, as little to no fission products would be deposited on the direct immediate area, instead becoming diluted global fallout.


title: Neutron bomb

text: However the most effective use of a neutron bomb with respect to area denial would be to encase it in a thick shell of material that could be neutron activated, and use a surface burst. In this manner the neutron bomb would be turned into a "salted bomb"; For example zinc-64, produced as a byproduct of depleted zinc oxide enrichment, would when neutron activated become zinc-65, which is a gamma emitter with a half life of 244 days.


title: Neutron bomb

text: With considerable overlap between the two devices, the prompt radiation effects of a pure fusion weapon would similarly be much higher than that of a pure-fission device: approximately twice the initial radiation output of current standard fission-fusion-based weapons. In common with all neutron bombs that must presently derive a small percentage of trigger energy from fission, in any given yield a 100% pure fusion bomb would likewise generate a smaller atmospheric blast wave than a "pure"-fission bomb. The latter fission device has a higher kinetic energy-ratio per unit of reaction energy released, which is most notable in the comparison with the D-T fusion reaction. A larger percentage of the energy from a D-T fusion reaction, is inherently put into uncharged neutron generation as opposed to charged particles, such as the alpha particle of the D-T reaction, the primary species, that is most responsible for the coulomb explosion/fireball.


title: Kurt Gödel

text: Kurt Friedrich Gödel ( , ; April 28, 1906 – January 14, 1978) was a logician, mathematician, and philosopher. Considered along with Aristotle and Gottlob Frege to be one of the most significant logicians in history, Gödel had an immense effect upon scientific and philosophical thinking in the 20th century, a time when others such as Bertrand Russell, Alfred North Whitehead, and David Hilbert were using logic and set theory to investigate the foundations of mathematics, building on earlier work by the likes of Richard Dedekind, Georg Cantor and Frege.


title: Kurt Gödel

text: Gödel published his first incompleteness theorem in 1931 when he was 25 years old, one year after finishing his doctorate at the University of Vienna. The first incompleteness theorem states that for any ω-consistent recursive axiomatic system powerful enough to describe the arithmetic of the natural numbers (for example Peano arithmetic), there are true propositions about the natural numbers that can be neither proved nor disproved from the axioms. To prove this, Gödel developed a technique now known as Gödel numbering, which codes formal expressions as natural numbers. The second incompleteness theorem, which follows from the first, states that the system cannot prove its own consistency.


title: Kurt Gödel

text: Gödel also showed that neither the axiom of choice nor the continuum hypothesis can be disproved from the accepted Zermelo–Fraenkel set theory, assuming that its axioms are consistent. The former result opened the door for mathematicians to assume the axiom of choice in their proofs. He also made important contributions to proof theory by clarifying the connections between classical logic, intuitionistic logic, and modal logic.


title: Kurt Gödel

text: Gödel was born April 28, 1906, in Brünn, Austria-Hungary (now Brno, Czech Republic) into the German-speaking family of Rudolf Gödel (1874–1929), the managing director and part owner of a major textile firm, and Marianne Gödel (née Handschuh, 1879–1966). At the time of his birth the city had a German-speaking majority which included his parents. His father was Catholic and his mother was Protestant and the children were raised Protestant. The ancestors of Kurt Gödel were often active in Brünn's cultural life. For example, his grandfather Joseph Gödel was a famous singer in his time and for some years a member of the (Men's Choral Union of Brünn).


title: Kurt Gödel

text: Gödel automatically became a citizen of Czechoslovakia at age 12 when the Austro-Hungarian Empire collapsed following its defeat in the First World War. According to his classmate , like many residents of the predominantly German , "Gödel considered himself always Austrian and an exile in Czechoslovakia". In February 1929, he was granted release from his Czechoslovakian citizenship and then, in April, granted Austrian citizenship. When Germany annexed Austria in 1938, Gödel automatically became a German citizen at age 32. In 1948, after World War II, at the age of 42, he became an American citizen.


title: Kurt Gödel

text: In his family, the young Gödel was nicknamed ("Mr. Why") because of his insatiable curiosity. According to his brother Rudolf, at the age of six or seven, Kurt suffered from rheumatic fever; he completely recovered, but for the rest of his life he remained convinced that his heart had suffered permanent damage. Beginning at age four, Gödel suffered from "frequent episodes of poor health", which would continue for his entire life.


title: Kurt Gödel

text: Gödel attended the , a Lutheran school in Brünn from 1912 to 1916, and was enrolled in the from 1916 to 1924, excelling with honors in all his subjects, particularly in mathematics, languages and religion. Although Gödel had first excelled in languages, he later became more interested in history and mathematics. His interest in mathematics increased when in 1920 his older brother Rudolf (born 1902) left for Vienna, where he attended medical school at the University of Vienna. During his teens, Gödel studied Gabelsberger shorthand, Goethe's "Theory of Colours" and criticisms of Isaac Newton, and the writings of Immanuel Kant.


title: Kurt Gödel

text: At the age of 18, Gödel joined his brother at the University of Vienna. By that time, he had already mastered university-level mathematics. Although initially intending to study theoretical physics, he also attended courses on mathematics and philosophy. During this time, he adopted ideas of mathematical realism. He read Kant's , and participated in the Vienna Circle with Moritz Schlick, Hans Hahn, and Rudolf Carnap. Gödel then studied number theory, but when he took part in a seminar run by Moritz Schlick which studied Bertrand Russell's book "Introduction to Mathematical Philosophy", he became interested in mathematical logic. According to Gödel, mathematical logic was "a science prior to all others, which contains the ideas and principles underlying all sciences."


title: Kurt Gödel

text: Attending a lecture by David Hilbert in Bologna on completeness and consistency in mathematical systems may have set Gödel's life course. In 1928, Hilbert and Wilhelm Ackermann published ("Principles of Mathematical Logic"), an introduction to first-order logic in which the problem of completeness was posed: "Are the axioms of a formal system sufficient to derive every statement that is true in all models of the system?"


title: Kurt Gödel

text: This problem became the topic that Gödel chose for his doctoral work. In 1929, at the age of 23, he completed his doctoral dissertation under Hans Hahn's supervision. In it, he established his eponymous completeness theorem regarding the first-order predicate calculus. He was awarded his doctorate in 1930, and his thesis (accompanied by some additional work) was published by the Vienna Academy of Science.


title: Kurt Gödel

text: In 1930 Gödel attended the Second Conference on the Epistemology of the Exact Sciences, held in Königsberg, 5–7 September. Here he delivered his incompleteness theorems.


title: Kurt Gödel

text: Gödel published his incompleteness theorems in (called in English "On Formally Undecidable Propositions of and Related Systems"). In that article, he proved for any computable axiomatic system that is powerful enough to describe the arithmetic of the natural numbers (e.g., the Peano axioms or Zermelo–Fraenkel set theory with the axiom of choice), that:


title: Kurt Gödel

text: These theorems ended a half-century of attempts, beginning with the work of Gottlob Frege and culminating in and Hilbert's Program, to find a non-relatively consistent axiomatization sufficient for number theory (that was to serve as the foundation for other fields of mathematics).


title: Kurt Gödel

text: In hindsight, the basic idea at the heart of the incompleteness theorem is rather simple. Gödel essentially constructed a formula that claims that it is unprovable in a given formal system. If it were provable, it would be false.


title: Kurt Gödel

text: That is, for any computably enumerable set of axioms for arithmetic (that is, a set that can in principle be printed out by an idealized computer with unlimited resources), there is a formula that is true of arithmetic, but which is not provable in that system.


title: Kurt Gödel

text: To make this precise, however, Gödel needed to produce a method to encode (as natural numbers) statements, proofs, and the concept of provability; he did this using a process known as Gödel numbering.


title: Kurt Gödel

text: In his two-page paper (1932) Gödel refuted the finite-valuedness of intuitionistic logic. In the proof, he implicitly used what has later become known as Gödel–Dummett intermediate logic (or Gödel fuzzy logic).


title: Kurt Gödel

text: Gödel earned his habilitation at Vienna in 1932, and in 1933 he became a (unpaid lecturer) there. In 1933 Adolf Hitler came to power in Germany, and over the following years the Nazis rose in influence in Austria, and among Vienna's mathematicians. In June 1936, Moritz Schlick, whose seminar had aroused Gödel's interest in logic, was assassinated by one of his former students, Johann Nelböck. This triggered "a severe nervous crisis" in Gödel. He developed paranoid symptoms, including a fear of being poisoned, and spent several months in a sanitarium for nervous diseases.


title: Kurt Gödel

text: In 1933, Gödel first traveled to the U.S., where he met Albert Einstein, who became a good friend. He delivered an address to the annual meeting of the American Mathematical Society. During this year, Gödel also developed the ideas of computability and recursive functions to the point where he was able to present a lecture on general recursive functions and the concept of truth. This work was developed in number theory, using Gödel numbering.


title: Kurt Gödel

text: In 1934, Gödel gave a series of lectures at the Institute for Advanced Study (IAS) in Princeton, New Jersey, titled "On undecidable propositions of formal mathematical systems". Stephen Kleene, who had just completed his PhD at Princeton, took notes of these lectures that have been subsequently published.


title: Kurt Gödel

text: Gödel visited the IAS again in the autumn of 1935. The travelling and the hard work had exhausted him and the next year he took a break to recover from a depressive episode. He returned to teaching in 1937. During this time, he worked on the proof of consistency of the axiom of choice and of the continuum hypothesis; he went on to show that these hypotheses cannot be disproved from the common system of axioms of set theory.


title: Kurt Gödel

text: He married (née Porkert, 1899–1981), whom he had known for over 10 years, on September 20, 1938. Gödel's parents had opposed their relationship because she was a divorced dancer, six years older than he was.


title: Kurt Gödel

text: Subsequently, he left for another visit to the United States, spending the autumn of 1938 at the IAS and publishing "Consistency of the axiom of choice and of the generalized continuum-hypothesis with the axioms of set theory," a classic of modern mathematics. In that work he introduced the constructible universe, a model of set theory in which the only sets that exist are those that can be constructed from simpler sets. Gödel showed that both the axiom of choice (AC) and the generalized continuum hypothesis (GCH) are true in the constructible universe, and therefore must be consistent with the Zermelo–Fraenkel axioms for set theory (ZF). This result has had considerable consequences for working mathematicians, as it means they can assume the axiom of choice when proving the Hahn–Banach theorem. Paul Cohen later constructed a model of ZF in which AC and GCH are false; together these proofs mean that AC and GCH are independent of the ZF axioms for set theory.


title: Kurt Gödel

text: Germany abolished the title , so Gödel had to apply for a different position under the new order. His former association with Jewish members of the Vienna Circle, especially with Hahn, weighed against him. The University of Vienna turned his application down.


title: Kurt Gödel

text: His predicament intensified when the German army found him fit for conscription. World War II started in September 1939.


title: Kurt Gödel

text: Before the year was up, Gödel and his wife left Vienna for Princeton. To avoid the difficulty of an Atlantic crossing, the Gödels took the Trans-Siberian Railway to the Pacific, sailed from Japan to San Francisco (which they reached on March 4, 1940), then crossed the US by train to Princeton. There Gödel accepted a position at the Institute for Advanced Study (IAS), which he had previously visited during 1933–34.


title: Kurt Gödel

text: Albert Einstein was also living at Princeton during this time. Gödel and Einstein developed a strong friendship, and were known to take long walks together to and from the Institute for Advanced Study. The nature of their conversations was a mystery to the other Institute members. Economist Oskar Morgenstern recounts that toward the end of his life Einstein confided that his "own work no longer meant much, that he came to the Institute merely ... to have the privilege of walking home with Gödel".


title: Kurt Gödel

text: Gödel and his wife, Adele, spent the summer of 1942 in Blue Hill, Maine, at the Blue Hill Inn at the top of the bay. Gödel was not merely vacationing but had a very productive summer of work. Using [volume 15] of Gödel's still-unpublished [working notebooks], John W. Dawson Jr. conjectures that Gödel discovered a proof for the independence of the axiom of choice from finite type theory, a weakened form of set theory, while in Blue Hill in 1942. Gödel's close friend Hao Wang supports this conjecture, noting that Gödel's Blue Hill notebooks contain his most extensive treatment of the problem.


title: Kurt Gödel

text: On December 5, 1947, Einstein and Morgenstern accompanied Gödel to his U.S. citizenship exam, where they acted as witnesses. Gödel had confided in them that he had discovered an inconsistency in the U.S. Constitution that could allow the U.S. to become a dictatorship; this has since been dubbed Gödel's Loophole. Einstein and Morgenstern were concerned that their friend's unpredictable behavior might jeopardize his application. The judge turned out to be Phillip Forman, who knew Einstein and had administered the oath at Einstein's own citizenship hearing. Everything went smoothly until Forman happened to ask Gödel if he thought a dictatorship like the Nazi regime could happen in the U.S. Gödel then started to explain his discovery to Forman. Forman understood what was going on, cut Gödel off, and moved the hearing on to other questions and a routine conclusion.


title: Kurt Gödel

text: Gödel became a permanent member of the Institute for Advanced Study at Princeton in 1946. Around this time he stopped publishing, though he continued to work. He became a full professor at the Institute in 1953 and an emeritus professor in 1976.


title: Kurt Gödel

text: During his time at the institute, Gödel's interests turned to philosophy and physics. In 1949, he demonstrated the existence of solutions involving closed timelike curves, to Einstein's field equations in general relativity. He is said to have given this elaboration to Einstein as a present for his 70th birthday. His "rotating universes" would allow time travel to the past and caused Einstein to have doubts about his own theory. His solutions are known as the Gödel metric (an exact solution of the Einstein field equation).


title: Kurt Gödel

text: He studied and admired the works of Gottfried Leibniz, but came to believe that a hostile conspiracy had caused some of Leibniz's works to be suppressed. To a lesser extent he studied Immanuel Kant and Edmund Husserl. In the early 1970s, Gödel circulated among his friends an elaboration of Leibniz's version of Anselm of Canterbury's ontological proof of God's existence. This is now known as Gödel's ontological proof.


title: Kurt Gödel

text: Gödel was awarded (with Julian Schwinger) the first Albert Einstein Award in 1951, and was also awarded the National Medal of Science, in 1974. Gödel was elected a resident member of the American Philosophical Society in 1961 and a Foreign Member of the Royal Society (ForMemRS) in 1968. He was a Plenary Speaker of the ICM in 1950 in Cambridge, Massachusetts. The Gödel Prize, an annual prize for outstanding papers in the area of theoretical computer science, is named after him.


title: Kurt Gödel

text: Later in his life, Gödel suffered periods of mental instability and illness. Following the assassination of his close friend Moritz Schlick, Gödel developed an obsessive fear of being poisoned, and would eat only food prepared by his wife Adele. Adele was hospitalized beginning in late 1977, and in her absence Gödel refused to eat; he weighed when he died of "malnutrition and inanition caused by personality disturbance" in Princeton Hospital on January 14, 1978. He was buried in Princeton Cemetery. Adele died in 1981.


title: Kurt Gödel

text: Gödel believed that God was personal, and called his philosophy "rationalistic, idealistic, optimistic, and theological".


title: Kurt Gödel

text: Gödel believed in an afterlife, saying, "Of course this supposes that there are many relationships which today's science and received wisdom haven't any inkling of. But I am convinced of this [the afterlife], independently of any theology." It is "possible today to perceive, by pure reasoning" that it "is entirely consistent with known facts." "If the world is rationally constructed and has meaning, then there must be such a thing [as an afterlife]."


title: Kurt Gödel

text: In an unmailed answer to a questionnaire, Gödel described his religion as "baptized Lutheran (but not member of any religious congregation). My belief is "theistic", not pantheistic, following Leibniz rather than Spinoza." Of religion(s) in general, he said: "Religions are, for the most part, bad—but religion is not". According to his wife Adele, "Gödel, although he did not go to church, was religious and read the Bible in bed every Sunday morning", while of Islam, he said, "I like Islam: it is a consistent [or consequential] idea of religion and open-minded."


title: Kurt Gödel

text: Douglas Hofstadter wrote the 1979 book to celebrate the work and ideas of Gödel, M. C. Escher and Johann Sebastian Bach. It partly explores the ramifications of the fact that Gödel's incompleteness theorem can be applied to any Turing-complete computational system, which may include the human brain.


title: Kurt Gödel

text: The Kurt Gödel Society, founded in 1987, was named in his honor. It is an international organization for the promotion of research in logic, philosophy, and the history of mathematics. The University of Vienna hosts the Kurt Gödel Research Center for Mathematical Logic. The Association for Symbolic Logic has invited an annual Kurt Gödel lecturer each year since 1990. Gödel's Philosophical Notebooks are edited at the Kurt Gödel Research Centre which is situated at the Berlin-Brandenburg Academy of Sciences and Humanities in Germany.


title: Kurt Gödel

text: Five volumes of Gödel's collected works have been published. The first two include his publications; the third includes unpublished manuscripts from his , and the final two include correspondence.


title: Kurt Gödel

text: In 2005 John Dawson published a biography of Gödel, "Logical Dilemmas: The Life and Work of Kurt Gödel" (A. K. Peters, Wellesley, MA, ). Stephen Budiansky's book about Gödel's life, "Journey to the Edge of Reason: The Life of Kurt Gödel" (W. W. Norton & Company, New York City, NY, ), was a "New York Times" Critics' Top Book of 2021.


title: Kurt Gödel

text: Gödel was also one of four mathematicians examined in David Malone's 2008 BBC documentary "Dangerous Knowledge".


title: Mass killings under communist regimes

text: Mass killings under communist regimes occurred through a variety of means during the 20th century, including executions, famine, deaths through forced labour, deportation, and imprisonment. Some of these events have been classified as genocides or crimes against humanity. Other terms have been used to describe these events, including classicide, democide, red holocaust, and politicide. The mass killings have been studied by authors and academics and several of them have postulated the potential causes of these killings along with the factors which were associated with them. Some authors have tabulated a total death toll, consisting of all of the excess deaths which cumulatively occurred under the rule of communist states, but these death toll estimates have been criticized. Most frequently, the states and events which are studied and included in death toll estimates are the Soviet Union, the Holodomor, and the Great Purge; the People's Republic of China and the Great Chinese Famine and the Cultural Revolution; and Democratic Kampuchea (now Cambodia) and the Cambodian genocide.


title: Mass killings under communist regimes

text: The concept of connecting disparate killings to the status of the communist states which committed them and the concept of trying to ascribe common causes and factors to them have both been supported and criticized by the academic community. Some academics view it as an indictment of communism as an ideology, while other academics view it as being overly simplistic and they also view it as being rooted in anti-communism. Instead, some academics attribute the causes of the killings to either the political systems or the leaders of the communist states. There is also debate over whether or not the famines which occurred during the rule of communist states can be considered mass killings. Mass killings which were committed by communist states have been compared to killings which were committed by other types of states.


title: Mass killings under communist regimes

text: Monuments to the victims of communism exist in almost all the capitals of Eastern Europe and in Washington, D.C. A memorial is currently under construction in Ottawa, Canada.


title: Mass killings under communist regimes

text: Several different terms are used to describe the intentional killing of large numbers of noncombatants. According to historian Anton Weiss-Wendt, the field of comparative genocide studies has very "little consensus on defining principles such as definition of genocide, typology, application of a comparative method, and timeframe." According to professor of economics Attiat Ott, "mass killing" has emerged as a "more straightforward" term.


title: Mass killings under communist regimes

text: The following terminology has been used by individual authors to describe mass killings of unarmed civilians by communist governments, individually or as a whole:


title: Mass killings under communist regimes

text: According to historian Klas-Göran Karlsson, discussions of the number of victims of communist regimes have been "extremely extensive and ideologically biased." Any attempt to estimate a total number of killings under communist regimes depends greatly on definitions, ranging from a low of 10–20 million to as high as 148 million. Political scientist Rudolph Rummel and historian Mark Bradley have written that, while the exact numbers have been in dispute, the order of magnitude is not. Professor Barbara Harff says that Rummel and other genocide scholars are focused primarily on establishing patterns and testing various theoretical explanations of genocides and mass killings. They work with large data sets that describe mass mortality events globally, and have to rely on selective data provided by country experts; researchers cannot expect absolute precision, and it is not required as a result of their work.


title: Mass killings under communist regimes

text: Any attempt to estimate a total number of killings under communist regimes depends greatly on definitions. Historian Alexander Dallin argued that the idea to group together different countries such as Afghanistan and Hungary has no adequate explanation. During the Cold War era, some authors (Todd Culberston), dissidents (Aleksandr Solzhenitsyn), and anti-communists in general have attempted to make both country-specific and global estimates. Scholars of communism have mainly focused on individual countries, and genocide scholars have attempted to provide a more global perspective, while maintaining that their goal is not reliability but establishing patterns. Scholars of communism have debated on estimates for the Soviet Union, not for all communist regimes, an attempt which was popularized by the introduction to "The Black Book of Communism" which was controversial. Among them, Soviet specialists Michael Ellman and J. Arch Getty have criticized the estimates for relying on "émigré" sources, hearsay, and rumor as evidence, and cautioned that historians should instead utilize archive material. Such scholars distinguish between historians who base their research on archive materials, and those whose estimates are based on witnesses evidence and other data that is unreliable. Soviet specialist Stephen G. Wheatcroft says that historians relied on Solzhenitsyn to support their higher estimates but research in the state archives vindicated the lower estimates, and that the popular press has continued to include serious errors that should not be cited, or relied on, in academia. Rummel was also another widely used and cited source but not reliable about estimates.


title: Mass killings under communist regimes

text: Criticism of the estimates are mostly focused on three aspects, namely that the estimates are based on sparse and incomplete data when significant errors are inevitable, the figures are skewed to higher possible values, and victims of civil wars, Holodomor, and other famines, and wars involving communist governments should not be counted. Criticism also includes that these estimates ignore lives saved by communist modernization and that they engage in comparisons and equations with Nazism, which are described by scholars as Holocaust obfuscation, Holocaust trivialization, and anti-communist oversimplifications. In addition, the communist grouping as applied by Courtois and Malia in "The Black Book of Communism" has been claimed to have no adequate explanation by historian Alexander Dallin, and Malia is able to link disparate regimes, from radical Soviet industrialists to the anti-urbanists of the Khmer Rouge, under the guise of a "generic communism" category "defined everywhere down to the common denominator of party movements founded by intellectuals." However, alongside philosopher Scott Sehon, Ghodsee wrote that "quibbling about numbers is unseemly. What matters is that many, many people were killed by communist regimes."


title: Mass killings under communist regimes

text: Criticism of Rummel's estimates have focused on two aspects, namely his choice of data sources and his statistical approach. According to Barbara Harff, the historical sources Rummel based his estimates upon can rarely serve as sources of reliable figures. The statistical approach Rummel used to analyze big sets of diverse estimates may lead to dilution of useful data with noisy ones.


title: Mass killings under communist regimes

text: Another criticism, as articulated by ethnographer and postsocialist gender studies scholar Kristen Ghodsee and political scientist Laure Neumayer, is that the body-counting reflects an anti-communist point of view, is mainly approached by anti-communist scholars, and is part of the popular "victims of communism" narrative, who have frequently used the 100 million figure from the introduction to "The Black Book of Communism", which is used not only to discredit the communist movement, but the whole political left. They say the same body-counting can be easily applied to other ideologies or systems, such as capitalism and colonialism.


title: Mass killings under communist regimes

text: Communist party mass killings have been criticized by members of the political right, who state that the mass killings are an indictment of communism as an ideology, and has also been criticized by other socialists such as anarchists, communists, democratic socialists, libertarian socialists, and Marxists. Opponents of this hypothesis, including those on the political left and communist party members, state that these killings were aberrations caused by specific authoritarian regimes, and not caused by communism itself, and point to mass deaths that they say were caused by anti-communism and capitalism as a counterpoint to those killings.


title: Mass killings under communist regimes

text: Historian Klas-Göran Karlsson writes: "Ideologies are systems of ideas, which cannot commit crimes independently. However, individuals, collectives and states that have defined themselves as communist have committed crimes in the name of communist ideology, or without naming communism as the direct source of motivation for their crimes." John Gray, Daniel Goldhagen, and Richard Pipes consider the ideology of communism to be a significant causative factor in mass killings. In the introduction to "The Black Book of Communism", Stéphane Courtois claims an association between communism and criminality, stating that "Communist regimes ... turned mass crime into a full-blown system of government", while adding that this criminality lies at the level of ideology rather than state practice.


title: Mass killings under communist regimes

text: Professor Mark Bradley writes that communist theory and practice has often been in tension with human rights and most communist states followed the lead of Karl Marx in rejecting "Enlightenment-era inalienable individual political and civil rights" in favor of "collective economic and social rights." Christopher J. Finlay posits that Marxism legitimates violence without any clear limiting principle because it rejects moral and ethical norms as constructs of the dominant class, and states that "it would be conceivable for revolutionaries to commit atrocious crimes in bringing about a socialist system, with the belief that their crimes will be retroactively absolved by the new system of ethics put in place by the proletariat." Rustam Singh states that Marx had alluded to the possibility of peaceful revolution; after the failed Revolutions of 1848, Singh states that Marx emphasized the need for violent revolution and "revolutionary terror".


title: Mass killings under communist regimes

text: Literary historian George Watson cited an 1849 article written by Friedrich Engels called "The Hungarian Struggle" and published in Marx's journal "Neue Rheinische Zeitung", and commented that "entire nations would be left behind after a workers' revolution against the bourgeoisie, feudal remnants in a socialist age, and since they could not advance two steps at a time, they would have to be killed. They were racial trash, as Engels called them, and fit only for the dung-heap of history." One book review criticized this interpretation, maintaining that "what Marx and Engels are calling for is ... at the very least a kind of cultural genocide; but it is not obvious, at least from Watson's citations, that actual mass killing, rather than (to use their phraseology) mere 'absorption' or 'assimilation', is in question." Talking about Engels' 1849 article, historian Andrzej Walicki states: "It is difficult to deny that this was an outright call for genocide." Jean-François Revel writes that Joseph Stalin recommended study of the 1849 Engels article in his 1924 book "On Lenin and Leninism".


title: Mass killings under communist regimes

text: According to Rummel, the killings committed by communist regimes can best be explained as the result of the marriage between absolute power and the absolutist ideology of Marxism. Rummel states that "communism was like a fanatical religion. It had its revealed text and its chief interpreters. It had its priests and their ritualistic prose with all the answers. It had a heaven, and the proper behavior to reach it. It had its appeal to faith. And it had its crusades against nonbelievers. What made this secular religion so utterly lethal was its seizure of all the state's instruments of force and coercion and their immediate use to destroy or control all independent sources of power, such as the church, the professions, private businesses, schools, and the family." Rummels writes that Marxist communists saw the construction of their utopia as "though a war on poverty, exploitation, imperialism and inequality. And for the greater good, as in a real war, people are killed. And, thus, this war for the communist utopia had its necessary enemy casualties, the clergy, bourgeoisie, capitalists, wreckers, counterrevolutionaries, rightists, tyrants, rich, landlords, and noncombatants that unfortunately got caught in the battle. In a war millions may die, but the cause may be well justified, as in the defeat of Hitler and an utterly racist Nazism. And to many communists, the cause of a communist utopia was such as to justify all the deaths."


title: Mass killings under communist regimes

text: Benjamin Valentino writes that "apparently high levels of political support for murderous regimes and leaders should not automatically be equated with support for mass killing itself. Individuals are capable of supporting violent regimes or leaders while remaining indifferent or even opposed to specific policies that these regimes and carried out." Valentino quotes Vladimir Brovkin as saying that "a vote for the Bolsheviks in 1917 was not a vote for Red Terror or even a vote for a dictatorship of the proletariat." According to Valentino, such strategies were so violent because they economically dispossess large numbers of people, commenting: "Social transformations of this speed and magnitude have been associated with mass killing for two primary reasons. First, the massive social dislocations produced by such changes have often led to economic collapse, epidemics, and, most important, widespread famines. ... The second reason that communist regimes bent on the radical transformation of society have been linked to mass killing is that the revolutionary changes they have pursued have clashed inexorably with the fundamental interests of large segments of their populations. Few people have proved willing to accept such far-reaching sacrifices without intense levels of coercion." According to Jacques Sémelin, "communist systems emerging in the twentieth century ended up destroying their own populations, not because they planned to annihilate them as such, but because they aimed to restructure the 'social body' from top to bottom, even if that meant purging it and recarving it to suit their new Promethean political "imaginaire.""


title: Mass killings under communist regimes

text: Daniel Chirot and Clark McCauley write that, especially in Joseph Stalin's Soviet Union, Mao Zedong's China, and Pol Pot's Cambodia, a fanatical certainty that socialism could be made to work motivated communist leaders in "the ruthless dehumanization of their enemies, who could be suppressed because they were 'objectively' and 'historically' wrong. Furthermore, if events did not work out as they were supposed to, then that was because class enemies, foreign spies and saboteurs, or worst of all, internal traitors were wrecking the plan. Under no circumstances could it be admitted that the vision itself might be unworkable, because that meant capitulation to the forces of reaction." Michael Mann writes that communist party members were "ideologically driven, believing that in order to create a new socialist society, they must lead in socialist zeal. Killings were often popular, the rank-and-file as keen to exceed killing quotas as production quotas." According to Vladimir Tismăneanu, "the Communist project, in such countries as the USSR, China, Cuba, Romania, or Albania, was based precisely on the conviction that certain social groups were irretrievably alien and deservedly murdered." Alex Bellamy writes that "communism's ideology of selective extermination" of target groups was first developed and applied by Joseph Stalin but that "each of the communist regimes that massacred large numbers of civilians during the Cold War developed their own distinctive account", while Steven T. Katz states that distinctions based on class and nationality, stigmatized and stereotyped in various ways, created an "otherness" for victims of communist rule that was important for legitimating oppression and death. Martin Shaw writes that "nationalist ideas were at the heart of many mass killings by Communist states", beginning with Stalin's "new nationalist doctrine of 'socialism in one country'", and killing by revolutionary movements in the Third World was done in the name of national liberation.


title: Mass killings under communist regimes

text: Anne Applebaum writes that "without exception, the Leninist belief in the one-party state was and is characteristic of every communist regime" and "the Bolshevik use of violence was repeated in every communist revolution." Phrases which were first uttered by Vladimir Lenin and Cheka founder Felix Dzerzhinsky were uttered all over the world. Applebaum states that as late as 1976, Mengistu Haile Mariam unleashed a Red Terror in Ethiopia. To his colleagues in the Bolshevik government, Lenin was quoted as saying: "If we are not ready to shoot a saboteur and White Guardist, what sort of revolution is that?".


title: Mass killings under communist regimes

text: Robert Conquest stated that Stalin's purges were not contrary to the principles of Leninism, rather, they were a natural consequence of the system which was established by Lenin, who personally ordered the killing of local groups of class enemy hostages. Alexander Nikolaevich Yakovlev, architect of perestroika and glasnost and later head of the Presidential Commission for the Victims of Political Repression, elaborates on this point, stating: "The truth is that in punitive operations Stalin did not think up anything that was not there under Lenin: executions, hostage taking, concentration camps, and all the rest." Historian Robert Gellately concurs, commenting: "To put it another way, Stalin initiated very little that Lenin had not already introduced or previewed."


title: Mass killings under communist regimes

text: Stephen Hicks of Rockford College ascribes the violence characteristic of 20th-century socialist rule to these collectivist regimes' abandonment of protections of civil rights and rejection of the values of civil society. Hicks writes that whereas "in practice every liberal capitalist country has a solid record for being humane, for by and large respecting rights and freedoms, and for making it possible for people to put together fruitful and meaningful lives", in socialism "practice has time and again proved itself more brutal than the worst dictatorships prior to the twentieth century. Each socialist regime has collapsed into dictatorship and begun killing people on a huge scale."


title: Mass killings under communist regimes

text: Eric D. Weitz states that the mass killing in communist states is a natural consequence of the failure of the rule of law, commonly seen during periods of social upheaval in the 20th century. For both communist and non-communist mass killings, "genocides occurred at moments of extreme social crisis, often generated by the very policies of the regimes", and are not inevitable but are political decisions. Steven Rosefielde writes that communist rulers had to choose between changing course and "terror-command" and more often than not, they chose the latter. Michael Mann posits that a lack of institutionalized authority structures meant that a chaotic mix of both centralized control and party factionalism were factors which contributed to the killings.


title: Mass killings under communist regimes

text: Professor Matthew Krain states that many scholars have pointed to revolutions and civil wars as providing the opportunity for radical leaders and ideologies to gain power and the preconditions for mass killing by the state. Professor Nam Kyu Kim writes that exclusionary ideologies are critical to explaining mass killing, but the organizational capabilities and individual characteristics of revolutionary leaders, including their attitudes towards risk and violence, are also important. Besides opening up political opportunities for new leaders to eliminate their political opponents, revolutions bring to power leaders who are more apt to commit large-scale acts of violence against civilians in order to legitimize and strengthen their own power. Genocide scholar Adam Jones states that the Russian Civil War was very influential on the emergence of leaders like Stalin and it also accustomed people to "harshness, cruelty, terror." Martin Malia called the "brutal conditioning" of the two World Wars important to understanding communist violence, although not its source.


title: Mass killings under communist regimes

text: Historian Helen Rappaport describes Nikolay Yezhov, the bureaucrat who was in charge of the NKVD during the Great Purge, as a physically diminutive figure of "limited intelligence" and "narrow political understanding. ... Like other instigators of mass murder throughout history, [he] compensated for his lack of physical stature with a pathological cruelty and the use of brute terror." Russian and world history scholar John M. Thompson places personal responsibility directly on Joseph Stalin. According to him, "much of what occurred only makes sense if it stemmed in part from the disturbed mentality, pathological cruelty, and extreme paranoia of Stalin himself. Insecure, despite having established a dictatorship over the party and country, hostile and defensive when confronted with criticism of the excesses of collectivization and the sacrifices required by high-tempo industrialization, and deeply suspicious that past, present, and even yet unknown future opponents were plotting against him, Stalin began to act as a person beleaguered. He soon struck back at enemies, real or imaginary." Professors Pablo Montagnes and Stephane Wolton posit that the purges in the Soviet Union and China can be attributed to the personalist leadership of Stalin and Mao, who were incentivized by having both control of the security apparatus used to carry out the purges and control of the appointment of replacements for those purged. Slovenian philosopher Slavoj Žižek attributes Mao allegedly viewing human life as disposable to his "cosmic perspective" on humanity.


title: Mass killings under communist regimes

text: American historian and author William Rubinstein wrote that "Most of the millions who perished at the hands of Stalin, Mao Tse-tung, Pol Pot and the other communist dictators died because the party's leaders believed they belonged to a dangerous or subversive social class or political grouping."


title: Mass killings under communist regimes

text: Daniel Goldhagen argues that 20th century communist regimes "have killed more people than any other regime type." Other scholars in the fields of communist studies and genocide studies, such as Steven Rosefielde and Benjamin Valentino, have come to similar conclusions. Rosefielde states that it is possible to conclude that the "Red Holocaust" killed more non-combatants than "Ha Shoah" and "Japan's Asian holocaust" combined, and it "was at least as heinous, given the "singularity" of Hitler's genocide." Rosefielde also writes that "while it is fashionable to mitigate the Red Holocaust by observing that capitalism killed millions of colonials in the twentieth century, primarily through man-made famines, no inventory of such felonious negligent homicides comes close to the Red Holocaust total."


title: Mass killings under communist regimes

text: Mark Aarons states that right-wing authoritarian regimes and dictatorships which were backed by Western powers committed atrocities and mass killings that rivaled the atrocities and mass killings that were committed in the communist world, citing examples such as the Indonesian occupation of East Timor, the Indonesian mass killings of 1965–1966, the "disappearances" in Guatemala during the civil war, and the assassinations and state terrorism that were associated with Operation Condor throughout South America. Vincent Bevins argues that the anti-communist mass killings that were perpetrated during the Cold War have been far more impactful on shaping the contemporary world than communist mass killings have been.


title: Mass killings under communist regimes

text: According to historian Christian Gerlach, communist mass killings were generally exceeded by atrocities which were committed by those who opposed them; he cites the crushing of the Paris Commune, the terrors of the Spanish Civil War, and the Indonesian mass killings of 1965–66 as examples, stating that "when both sides engaged in terror, the 'red' terror usually paled in comparison with the 'white."


title: Mass killings under communist regimes

text: According to historian J. Arch Getty, over half of the 100 million deaths which are attributed to communism were due to famines. Stéphane Courtois posits that many communist regimes caused famines in their efforts to forcibly collectivize agriculture and systematically used it as a weapon by controlling the food supply and distributing food on a political basis. Courtois states that "in the period after 1918, only communist countries experienced such famines, which led to the deaths of hundreds of thousands, and in some cases millions, of people. And again in the 1980s, two African countries that claimed to be Marxist–Leninist, Ethiopia and Mozambique, were the only such countries to suffer these deadly famines."


title: Mass killings under communist regimes

text: Stephen G. Wheatcroft, R. W. Davies, and Mark Tauger reject the idea that the Ukrainian famine was an act of genocide that was intentionally inflicted by the Soviet government. Wheatcroft says that the Soviet government's policies during the famine were criminal acts of fraud and manslaughter, though not outright murder or genocide. Joseph Stalin biographer Stephen Kotkin supports a similar view, stating that while "there is no question of Stalin's responsibility for the famine" and many deaths could have been prevented if not for the "insufficient" and counterproductive Soviet measures, there is no evidence for Stalin's intention to kill the Ukrainians deliberately. According to history professor Ronald Grigor Suny, most scholars view the famine in Ukraine not as a genocide but rather as the result of badly conceived and miscalculated Soviet economic policies. Getty posits that the "overwhelming weight of opinion among scholars working in the new archives is that the terrible famine of the 1930s was the result of Stalinist bungling and rigidity rather than some genocidal plan." In 2008, the Russian Duma also denied that the famine in Ukraine constituted a genocide, stating that it was not designed to target particular ethnic groups.


title: Mass killings under communist regimes

text: In contrast, according to Simon Payaslian, a scholarly consensus classifies the Holodomor in the former Soviet Ukraine as a genocide. Some historians conclude that the famine was planned and exacerbated by Joseph Stalin in order to eliminate a Ukrainian independence movement. This conclusion is supported by Raphael Lemkin. Lemkin (who coined the term "genocide" and was an initiator of the Genocide Convention), James Mace, Norman Naimark, Timothy Snyder and Anne Applebaum have called the Holodomor a genocide and the intentional result of Stalinist policies. According to Lemkin, Holodomor "is a classic example of the Soviet genocide, the longest and most extensive experiment in Russification, namely the extermination of the Ukrainian nation". Lemkin stated that, because Ukrainians were very vulnerable to the racial murder of its chosen parts and way too populous, the government could not follow the pattern of the Holocaust. Instead the extermination consisted of four steps: 1) extermination of the Ukrainian national elite 2) liquidation of the Ukrainian Autocephalous Orthodox Church 3) extermination of a significant part of the Ukrainian peasantry as "custodians of traditions, folklore and music, national language and literature 4) populating the territory with other nationalities with intent of mixing Ukrainians with them, which would eventually lead to the dissolvance of the Ukrainian nation.


title: Mass killings under communist regimes

text: Benjamin Valentino writes: "Although not all the deaths due to famine in these cases were intentional, communist leaders directed the worst effects of famine against their suspected enemies and used hunger as a weapon to force millions of people to conform to the directives of the state." Daniel Goldhagen says that in some cases deaths from famine should not be distinguished from mass murder, commenting: "Whenever governments have not alleviated famine conditions, political leaders decided not to say no to mass death – in other words, they said yes." Goldhagen says that instances of this occurred in the Mau Mau rebellion, the Great Leap Forward, the Nigerian Civil War, the Eritrean War of Independence, and the War in Darfur. Martin Shaw posits that if a leader knew the ultimate result of their policies would be mass death by famine, and they continue to enact them anyway, these deaths can be understood as intentional.


title: Mass killings under communist regimes

text: Historian Jon Wiener and journalist and Labour aide Seumas Milne, have criticized the emphasis on communism when assigning blame for famines. In a 2002 article for "The Guardian", Milne mentions "the moral blindness displayed towards the record of colonialism", and he writes: "If Lenin and Stalin are regarded as having killed those who died of hunger in the famines of the 1920s and 1930s, then Churchill is certainly responsible for the 4 million deaths in the avoidable Bengal famine of 1943." Milne laments that while "there is a much-lauded "Black Book of Communism", [there exists] no such comprehensive indictment of the colonial record." Weiner makes a similar assertion while comparing the Holodomor and the Bengal famine of 1943, stating that Winston Churchill's role in the Bengal famine "seems similar to Stalin's role in the Ukrainian famine." Historian Mike Davis, author of "Late Victorian Holocausts", draws comparisons between the Great Chinese Famine and the Indian famines of the late 19th century, arguing that in both instances the governments which oversaw the response to the famines deliberately chose not to alleviate conditions and as such bear responsibility for the scale of deaths in said famines. Economic anthropologist Jason Hickel and Dylan Sullivan suggest that the number excess deaths during the apex of British colonialism in India rise to around 100 million, which is greater than all the famine deaths that have been attributed to communist governments combined.


title: Mass killings under communist regimes

text: Economics professor Michael Ellman is critical of the fixation on a "uniquely Stalinist evil" when it comes to excess deaths from famines. Ellman posits that mass deaths from famines are not a "uniquely Stalinist evil", commenting that throughout Russian history, famines, and droughts have been a common occurrence, including the Russian famine of 1921–1922, which occurred before Stalin came to power. He also states that famines were widespread throughout the world in the 19th and 20th centuries in countries such as India, Ireland, Russia and China. According to Ellman, the G8 "are guilty of mass manslaughter or mass deaths from criminal negligence because of their not taking obvious measures to reduce mass deaths" and Stalin's "behaviour was no worse than that of many rulers in the nineteenth and twentieth centuries."


title: Mass killings under communist regimes

text: Monuments to the victims of communism exist in almost all the capitals of Eastern Europe and there are also several museums which document the crimes which occurred during communist rule such as the Museum of Occupations and Freedom Fights in Lithuania, the Museum of the Occupation of Latvia in Riga and the House of Terror in Budapest, all three of these museums also document the crimes which occurred during Nazi rule. Several scholars, among them Kristen Ghodsee and Laure Neumayer, posit that these efforts seek to institutionalize the "victims of communism" narrative as a double genocide theory, or the moral equivalence between the Nazi Holocaust (race murder) and those killed by communist states (class murder), and that works such as "The Black Book of Communism" played a major role in the criminalization of communism in the European political space in the post Cold War-era. Zoltan Dujisin writes that "the Europeanization of an antitotalitarian 'collective memory' of communism reveals the emergence of a field of anticommunism" and the narrative is proposed by "anticommunist memory entrepreneurs."


title: Mass killings under communist regimes

text: In Washington, D.C., a bronze statue modeled after the "Goddess of Democracy" sculpture, which was created during the 1989 Tiananmen Square protests, was dedicated as the Victims of Communism Memorial in 2007, having been authorized by the Congress in 1993. In 2022, the Victims of Communism Memorial Foundation opened an International Museum on Communism in Washington, D.C. In 2002, the Memorial to the Victims of Communism was unveiled in Prague. In Hungary, the Gloria Victis Memorial to honor "the 100 million victims of communism" was erected in 2006 on the 50th anniversary of the Hungarian Revolution. As of 2008, Russia contained 627 memorials and memorial plaques which are dedicated to the victims of the communist terror, most of them were created by private citizens, but it did not have either a national monument or a national museum. The Wall of Grief in Moscow, inaugurated in October 2017, is Russia's first monument to the victims of political persecution by Stalin during the country's Soviet era. In 2017, Canada's National Capital Commission approved the design of the Memorial to the Victims of Communism – Canada, a Land of Refuge which will be built on the Garden of the Provinces and Territories in Ottawa. On 23 August 2018, Estonia's Victims of Communism 1940–1991 Memorial was inaugurated in Tallinn by Estonian president Kersti Kaljulaid. The memorial's construction was financed by the state and the memorial itself is being managed by the Estonian Institute of Historical Memory. The date of the opening ceremony was chosen because it coincided with the official European Day of Remembrance for the Victims of Stalinism and Nazism.


title: Idealism

text: In philosophy, the term idealism identifies and describes metaphysical perspectives which assert that reality is indistinguishable and inseparable from perception and understanding; that reality is a mental construct closely connected to ideas. Idealist perspectives are in two categories: subjective idealism, which proposes that a material object exists only to the extent that a human being perceives the object; and objective idealism, which proposes the existence of an "objective" consciousness that exists prior to and independently of human consciousness, thus the existence of the object is independent of human perception.


title: Idealism

text: The philosopher George Berkeley said that the essence of an object is to be perceived. By contrast, Immanuel Kant said that idealism "does not concern the existence of things", but that "our modes of representation" of things such as "space" and "time" are not "determinations that belong to things in themselves", but are essential features of the human mind. In the philosophy of "transcendental idealism" Kant proposes that the objects of experience relied upon their existence in the human mind that perceives the objects, and that the nature of the thing-in-itself is external to human experience, and cannot be conceived without the application of categories, which give structure to the human experience of reality.


title: Idealism

text: Epistemologically, idealism is accompanied by philosophical skepticism about the possibility of knowing the existence of any "thing" that is independent of the human mind. Ontologically, idealism asserts that the existence of things depends upon the human mind; thus, ontological idealism rejects the perspectives of physicalism and dualism, because neither perspective gives ontological priority to the human mind. In contrast to materialism, idealism asserts the "primacy" of consciousness as the origin and prerequisite of phenomena. Idealism holds that consciousness (the mind) is the origin of the material world.


title: Idealism

text: Indian and Greek philosophers proposed the earliest arguments that the world of experience is grounded in the mind's perception of the physical world. Hindu idealism and Greek neoplatonism gave panentheistic arguments for the existence of an all-pervading consciousness as the true nature, as the true grounding of reality. In contrast, the Yogācāra school, which arose within Mahayana Buddhism in India in the 4th century AD, based its "mind-only" idealism to a greater extent on phenomenological analyses of personal experience. This turn toward the subjective anticipated empiricists such as George Berkeley, who revived idealism in 18th-century Europe by employing skeptical arguments against materialism. Beginning with Kant, German idealists such as Georg Wilhelm Friedrich Hegel, Johann Gottlieb Fichte, Friedrich Wilhelm Joseph Schelling, and Arthur Schopenhauer dominated 19th-century philosophy. This tradition, which emphasized the mental or "ideal" character of all phenomena, gave birth to idealistic and subjectivist schools ranging from British idealism to phenomenalism to existentialism.


title: Idealism

text: Idealism as a philosophy came under heavy attack in the West at the turn of the 20th century. The most influential critics of both epistemological and ontological idealism were G. E. Moore and Bertrand Russell, but its critics also included the new realists. According to "Stanford Encyclopedia of Philosophy", the attacks by Moore and Russell were so influential that even more than 100 years later "any acknowledgment of idealistic tendencies is viewed in the English-speaking world with reservation". However, many aspects and paradigms of idealism did still have a large influence on subsequent philosophy. Phenomenology, an influential strain of philosophy since the beginning of the 20th century, also draws on the lessons of idealism. In his "Being and Time", Martin Heidegger famously states:


title: Idealism

text: "Idealism" is a term with several related meanings. It comes via Latin "idea" from the Ancient Greek "idea" (ἰδέα) from "idein" (ἰδεῖν), meaning 'to see'. The term entered the English language by 1743. It was first used in the abstract metaphysical sense "belief that reality is made up only of ideas" by Christian Wolff in 1747. The term re-entered the English language in this abstract sense by 1796.


title: Idealism

text: In ordinary language, as when speaking of Woodrow Wilson's political idealism, it generally suggests the priority of ideals, principles, values, and goals over concrete realities. Idealists are understood to represent the world as it might or should be, unlike pragmatists, who focus on the world as it presently is. In the arts, similarly, idealism affirms imagination and attempts to realize a mental conception of beauty, a standard of perfection, juxtaposed to aesthetic naturalism and realism. The term "idealism" is also sometimes used in a sociological sense, which emphasizes how human ideas—especially beliefs and values—shape society.


title: Idealism

text: Any philosophy that assigns crucial importance to the ideal or spiritual realm in its account of human existence may be termed "idealist". Metaphysical idealism is an ontological doctrine that holds that reality itself is incorporeal or experiential at its core. Beyond this, idealists disagree on which aspects of the mental are more basic. Platonic idealism affirms that abstractions are more basic to reality than the things we perceive, while subjective idealists and phenomenalists tend to privilege sensory experience over abstract reasoning. Epistemological idealism is the view that reality can only be known through ideas, that only psychological experience can be apprehended by the mind.


title: Idealism

text: Subjective idealists like George Berkeley are anti-realists in terms of a mind-independent world. However, not all idealists restrict the real or the knowable to our immediate subjective experience. Objective idealists make claims about a transempirical world, but simply deny that this world is essentially divorced from or ontologically prior to the mental. Thus, Plato and Gottfried Leibniz affirm an objective and knowable reality transcending our subjective awareness—a rejection of epistemological idealism—but propose that this reality is grounded in ideal entities, a form of metaphysical idealism. Nor do all metaphysical idealists agree on the nature of the ideal; for Plato, the fundamental entities were non-mental abstract forms, while for Leibniz they were proto-mental and concrete monads.


title: Idealism

text: As a rule, transcendental idealists like Kant affirm idealism's epistemic side without committing themselves to whether reality is "ultimately" mental; objective idealists like Plato affirm reality's metaphysical basis in the mental or abstract without restricting their epistemology to ordinary experience; and subjective idealists like Berkeley affirm both metaphysical and epistemological idealism.


title: Idealism

text: Idealism as a form of metaphysical monism holds that consciousness, not matter, is the ground of all being. It is monist because it holds that there is only one type of thing in the universe and idealist because it holds that one thing to be consciousness.


title: Idealism

text: Anaxagoras (480 BC) taught that "all things" were created by "Nous" ("Mind"). He held that Mind held the cosmos together and gave human beings a connection to the cosmos or a pathway to the divine.


title: Idealism

text: Plato's theory of forms or "ideas" describes ideal forms (for example the platonic solids in geometry or abstracts like Goodness and Justice), as universals existing independently of any particular instance. Arne Grøn calls this doctrine "the classic example of a metaphysical idealism as a "transcendent" idealism", while Simone Klein calls Plato "the earliest representative of metaphysical objective idealism". Nevertheless, Plato holds that matter is real, though transitory and imperfect, and is perceived by our body and its senses and given existence by the eternal ideas that are perceived directly by our rational soul. Plato was therefore a metaphysical and epistemological dualist, an outlook that modern idealism has striven to avoid: Plato's thought cannot therefore be counted as idealist in the modern sense.


title: Idealism

text: With the neoplatonist Plotinus, wrote Nathaniel Alfred Boll "there even appears, probably for the first time in Western philosophy, "idealism" that had long been current in the East even at that time, for it taught... that the soul has made the world by stepping from eternity into time...". Similarly, in regard to passages from the Enneads, "The only space or place of the world is the soul" and "Time must not be assumed to exist outside the soul". Ludwig Noiré wrote: "For the first time in Western philosophy we find idealism proper in Plotinus". However, Plotinus does not address whether we know external objects, unlike Schopenhauer and other modern philosophers.


title: Idealism

text: Christian theologians have held idealist views, often based on neoplatonism, despite the influence of Aristotelian scholasticism from the 12th century onward. However, there is certainly a sense in which the scholastics retained the idealism that came via St. Augustine right back to Plato.


title: Idealism

text: Later western theistic idealism such as that of Hermann Lotze offers a theory of the "world ground" in which all things find their unity: it has been widely accepted by Protestant theologians. Several modern religious movements, for example the organizations within the New Thought Movement and the Unity Church, may be said to have a particularly idealist orientation. The theology of Christian Science includes a form of idealism: it teaches that all that truly exists is God and God's ideas; that the world as it appears to the senses is a distortion of the underlying spiritual reality, a distortion that may be corrected (both conceptually and in terms of human experience) through a reorientation (spiritualization) of thought.


title: Idealism

text: Wang Yangming, a Ming Chinese neo-Confucian philosopher, official, educationist, calligraphist and general, held that objects do not exist entirely apart from the mind because the mind shapes them. It is not the world that shapes the mind but the mind that gives reason to the world, so the mind alone is the source of all reason, having an inner light, an innate moral goodness and understanding of what is good.


title: Idealism

text: There are currents of idealism throughout Indian philosophy, ancient and modern. Hindu idealism often takes the form of monism or non-dualism, espousing the view that a unitary consciousness is the essence or meaning of the phenomenal reality and plurality.


title: Idealism

text: Buddhist idealism on the other hand is more epistemic and is not a metaphysical monism, which Buddhists consider eternalistic and hence not the Middle Way between extremes espoused by the Buddha.


title: Idealism

text: The oldest reference to Idealism in Vedic texts is in Purusha Sukta of the Rig Veda. This Sukta espouses panentheism by presenting cosmic being Purusha as both pervading all universe and yet being transcendent to it. Absolute idealism can be seen in Chāndogya Upaniṣad, where things of the objective world like the five elements and the subjective world such as will, hope, memory etc. are seen to be emanations from the Self.


title: Idealism

text: Idealist notions have been propounded by the Vedanta schools of thought, which use the Vedas, especially the Upanishads as their key texts. Idealism was opposed by dualists Samkhya, the atomists Vaisheshika, the logicians Nyaya, the linguists Mimamsa and the materialists Cārvāka. There are various sub schools of Vedanta, like Advaita Vedanta (non-dual), Vishishtadvaita and Bhedabheda Vedanta (difference and non-difference).


title: Idealism

text: The schools of Vedanta all attempt to explain the nature and relationship of Brahman (universal soul or Self) and Atman (individual self), which they see as the central topic of the Vedas. One of the earliest attempts at this was Bādarāyaņa's Brahma Sutras, which is canonical for all Vedanta sub-schools. Advaita Vedanta is a major sub school of Vedanta which holds a non-dual Idealistic metaphysics. According to Advaita thinkers like Adi Shankara (788–820) and his contemporary Maṇḍana Miśra, Brahman, the single unitary consciousness or absolute awareness, appears as the diversity of the world because of "maya" or illusion, and hence perception of plurality is "mithya", error. The world and all beings or souls in it have no separate existence from Brahman, universal consciousness, and the seemingly independent soul ("jiva") is identical to Brahman. These doctrines are represented in verses such as "brahma satyam jagan mithya; jīvo brahmaiva na aparah" (Brahman is alone True, and this world of plurality is an error; the individual self is not different from Brahman). Other forms of Vedanta like the Vishishtadvaita of Ramanuja and the Bhedabheda of Bhāskara are not as radical in their non-dualism, accepting that there is a certain difference between individual souls and Brahman. Dvaita school of Vedanta by Madhvacharya maintains the opposing view that the world is real and eternal. It also argues that real Atman fully depends on the reflection of independent Brahman.


title: Idealism

text: The Tantric tradition of Kashmir Shaivism has also been categorized by scholars as a form of Idealism. The key thinker of this tradition is the Kashmirian Abhinavagupta (975–1025 CE).


title: Idealism

text: Modern Vedic Idealism was defended by the influential Indian philosopher Sarvepalli Radhakrishnan in his 1932 "An Idealist View of Life" and other works, which espouse Advaita Vedanta. The essence of Hindu Idealism is captured by such modern writers as Sri Nisargadatta Maharaj, Sri Aurobindo, P. R. Sarkar, and Sohail Inayatullah.


title: Idealism

text: Buddhist views which can be said to be similar to Idealism appear in Mahayana Buddhist texts such as the Samdhinirmocana sutra, Laṅkāvatāra Sūtra, Dashabhumika sutra, etc. These were later expanded upon by Indian Buddhist philosophers of the influential Yogacara school, like Vasubandhu, Asaṅga, Dharmakīrti, and Śāntarakṣita. Yogacara thought was also promoted in China by Chinese philosophers and translators like Xuanzang.


title: Idealism

text: There is a modern scholarly disagreement about whether Yogacara Buddhism can be said to be a form of idealism. As Saam Trivedi notes: "on one side of the debate, writers such as Jay Garfield, Jeffrey Hopkins, Paul Williams, and others maintain the idealism label, while on the other side, Stefan Anacker, Dan Lusthaus, Richard King, Thomas Kochumuttom, Alex Wayman, Janice Dean Willis, and others have argued that Yogacara is not idealist." The central point of issue is what Buddhist philosophers like Vasubandhu who used the term "vijñapti-matra" ("representation-only" or "cognition-only") and formulated arguments to refute external objects actually meant to say.


title: Idealism

text: Vasubandhu's works include a refutation of external objects or externality itself and argues that the true nature of reality is beyond subject-object distinctions. He views ordinary consciousness experience as deluded in its perceptions of an external world separate from itself and instead argues that all there is "Vijñapti" (representation or conceptualization). Hence Vasubandhu begins his "Vimsatika" with the verse: "All this is consciousness-only, because of the appearance of non-existent objects, just as someone with an optical disorder may see non-existent nets of hair."


title: Idealism

text: Likewise, the Buddhist philosopher Dharmakirti's view of the apparent existence of external objects is summed up by him in the Pramānaṿārttika ('Commentary on Logic and Epistemology'): "Cognition experiences itself, and nothing else whatsoever. Even the particular objects of perception, are by nature just consciousness itself."


title: Idealism

text: While some writers like Jay Garfield hold that Vasubandhu is a metaphysical idealist, others see him as closer to an epistemic idealist like Kant who holds that our knowledge of the world is simply knowledge of our own concepts and perceptions of a transcendental world. Sean Butler upholding that Yogacara is a form of idealism, albeit its own unique type, notes the similarity of Kant's categories and Yogacara's "Vāsanās", both of which are simply phenomenal tools with which the mind interprets the noumenal realm. Unlike Kant however who holds that the noumenon or thing-in-itself is unknowable to us, Vasubandhu holds that ultimate reality is knowable, but only through non-conceptual yogic perception of a highly trained meditative mind.


title: Idealism

text: Writers like Dan Lusthaus who hold that Yogacara is not a metaphysical idealism point out, for example, that Yogācāra thinkers did not focus on consciousness to assert it as ontologically real, but simply to analyze how our experiences and thus our suffering is created. As Lusthaus notes: "no Indian Yogācāra text ever claims that the world is created by mind. What they do claim is that we mistake our projected interpretations of the world for the world itself, i.e. we take our own mental constructions to be the world." Lusthaus notes that there are similarities to Western epistemic idealists like Kant and Husserl, enough so that Yogacara can be seen as a form of epistemological idealism. However he also notes key differences like the concepts of karma and nirvana. Saam Trivedi meanwhile notes the similarities between epistemic idealism and Yogacara, but adds that Yogacara Buddhism is in a sense its own theory.


title: Idealism

text: Similarly, Thomas Kochumuttom sees Yogacara as "an explanation of experience, rather than a system of ontology" and Stefan Anacker sees Vasubandhu's philosophy as a form of psychology and as a mainly therapeutic enterprise.


title: Idealism

text: Subjective idealism (also known as immaterialism) describes a relationship between experience and the world in which objects are no more than collections or bundles of sense data in the perceiver. Proponents include Berkeley, Bishop of Cloyne, an Anglo-Irish philosopher who advanced a theory he called "immaterialism," later referred to as "subjective idealism", contending that individuals can only know sensations and ideas of objects directly, not abstractions such as "matter", and that ideas also depend upon being perceived for their very existence - "esse est percipi"; "to be is to be perceived".


title: Idealism

text: Arthur Collier published similar assertions though there seems to have been no influence between the two contemporary writers. The only knowable reality is the represented image of an external object. Matter as a cause of that image, is unthinkable and therefore nothing to us. An external world as absolute matter unrelated to an observer does not exist as far as we are concerned. The universe cannot exist as it appears if there is no perceiving mind. Collier was influenced by "An Essay Towards the Theory of the Ideal or Intelligible World" by Cambridge Platonist John Norris (1701).


title: Idealism

text: Paul Brunton, a British philosopher, mystic, traveler, and guru, taught a type of idealism called "mentalism," similar to that of Bishop Berkeley, proposing a master world-image, projected or manifested by a world-mind, and an infinite number of individual minds participating. A tree does not cease to exist if nobody sees it because the world-mind is projecting the idea of the tree to all minds


title: Idealism

text: Epistemological idealism is a subjectivist position in epistemology that holds that what one knows about an object exists only in one's mind. Proponents include Brand Blanshard.


title: Idealism

text: A. A. Luce and John Foster are other subjectivists. Luce, in "Sense without Matter" (1954), attempts to bring Berkeley up to date by modernizing his vocabulary and putting the issues he faced in modern terms, and treats the Biblical account of matter and the psychology of perception and nature. Foster's "The Case for Idealism" argues that the physical world is the logical creation of natural, non-logical constraints on human sense-experience. Foster's latest defense of his views (phenomenalistic idealism) is in his book "A World for Us: The Case for Phenomenalistic Idealism".


title: Idealism

text: Critics of Subjective idealism include Bertrand Russell's popular 1912 book "The Problems of Philosophy", Australian philosopher David Stove, Alan Musgrave, and John Searle.


title: Idealism

text: Transcendental idealism, founded by Immanuel Kant in the eighteenth century, maintains that the mind shapes the world we perceive into the form of space-and-time.