AutoPlay.

AutoPlay is a feature introduced in Windows XP which examines removable media and devices and, based on content such as pictures, music or video files, launches an appropriate application to play or display the content. If available, settings in an autorun.inf file can add to the options presented to the user.  AutoPlay is based on a set of handler applications registered with the AutoPlay system. Each media type (Pictures, Music, Video) can have a set of registered handlers which can deal with playing or display that type of media.  Each hardware device can have a default action occurring on discovery of a particular media type, or the AutoPlay dialog can prompt the user what action to take.

AutoRun activation.

The AutoRun sequence starts with the initial discovery of a new device or new piece of media. Following this, notification of interested parties occurs, of which the Windows Explorer shell is of primary interest. After checking certain Registry settings to see if AutoRun can proceed, parsing of an optional autorun.inf may occur and any necessary actions are taken.  The initial sequence is handled much the same in every version of Windows from Windows 95. However, the way the autorun.inf file is read and acted upon and the level of integration of AutoRun with AutoPlay has changed significantly from the time AutoPlay was introduced in Windows XP until the present handling in Windows 7. In Windows 10, Microsoft has added the option to enable autorun in its settings. Not only users can turn it on but also they can choose specific external devices for autoplay.

Initiation and notification.

When a device with AutoRun-compatible drivers receives new media, a "Media Change Notification" event occurs. The Windows OS then notifies interested applications that a device change has occurred. The notification method used can change depending on the device type.  If the device changed is a volume (like a CD) or a port (like a serial port) Windows broadcasts a notification to all top-level windows. Windows calls this a "basic" notification. A top-level window is one which is a descendant of the desktop.  However, if the device changed is not one of these types an application can use the function to register to receive device notifications. An article on the CodeProject website, "Detecting Hardware Insertion and/or Removal", with clarifications from a blog by Doran Holan is of particular technical interest here. Non-volume devices are those devices that do not appear as drive letters in "My Computer". These are not handled by any part of AutoRun - any actions taken for these devices are taken either by device specific software or by AutoPlay. See AutoPlay#Devices that are not drives.  When Explorer receives notification of a "volume" change, it performs a number of actions:

Changing behaviour.

Before AutoPlay.

On Windows versions prior to Windows XP, an autorun.inf file on any drive type will be read and its instructions followed. The AutoRun task, if specified, is executed immediately without user interaction. This includes DRIVE_REMOVABLE, DRIVE_FIXED and DRIVE_REMOTE drive types.  AutoRun will work with network drives (the DRIVE_REMOTE drive type) that are mapped to a drive letter. AutoRun will also work with floppy drives that are provided with autorun-compatible drivers.  The default Registry settings on Windows versions prior to Windows XP (See NoDriveTypeAutoRun), disable Remote and Removable drives from AutoRun initiation, leaving Fixed and CDROM drive types active by default.

Introducing AutoPlay.

With the introduction of AutoPlay in Windows XP, the final stage action (stage 7 above) for some drive types changed from executing an application to invoking AutoPlay. From Windows Vista, the AutoPlay system is integrated into every aspect of media handling and there is no automatic execution of the AutoRun task.  The default Registry settings add Removable drives to those that initiated AutoRun. In Windows XP and higher, "except" Windows Server 2003, only the Unknown and Remote drive types are not active for AutoRun.  The handling of the autorun.inf file changes very significantly between each Windows version. The details can be found in the autorun.inf article. The current handling in Windows 7 is that "only" drives of type DRIVE_CDROM may specify an AutoRun task, alter double-click behaviour or change context menus.

Registry settings.

AutoRun consults Windows Registry values to decide whether to initiate actions for any particular drive or drive type. These values can be changed using several methods, one of which is using Group Policy.  The primary relevant Registry entry names are and. These exist in both per-machine and per-user settings and their location and priority in the Registry are described in further detail below.

Drive types.

The drive types are distinguished by Type Name as follows:

Registry terminology.

The Windows Registry is a hierarchical database that stores configuration settings and options for the operating system. The terminology is somewhat misleading so it is briefly summarised here.  A Registry "key" is similar to a folder that, in addition to values, each key can contain subkeys which in turn may contain subkeys, and so on.  A Registry "value" consists of a name-data pair. Microsoft documentation commonly uses the term "entry" as an equivalent term. It also uses "value" for "data" when it is obvious what is meant. To avoid confusion, this article always uses the term "entry" when referring to the name-data pair.  Two Registry keys that are very commonly referred to are which contains per-machine settings, and which contains settings for the currently logged-on user. These are almost always abbreviated as and respectively. There may be many users of a machine; their settings are stored in, is actually just a link to the appropriate place in.

Changing Registry settings.

Registry settings may be changed directly by using the GUI tool or the command line utility. Settings can also be placed in a text file, named with a.reg extension type. For example, "". When the file is double clicked, the settings in the file are entered into the Registry, permissions allowing.  They can be changed indirectly by using Group Policy, applied locally to a single computer with or to a domain with.  It may be necessary to either logout or restart the computer in order for any Registry changes to take effect.

Evaluation order.

The and Registry entries can exist in two places, the per-user setting (under HKEY_CURRENT_USER) and the per-machine setting (under HKEY_LOCAL_MACHINE). If an entry appears under HKEY_LOCAL_MACHINE, then any corresponding entry under HKEY_CURRENT_USER is completely ignored. The data values are not merged in any way.  When deciding whether to activate AutoRun, both and Registry entries are consulted. If either value indicates a drive should be disabled then AutoRun is disabled for that drive.  Thus in the following example:  the data value taken for is 0x08, disabling drive D and the data value taken for is 0x95, disabling removable and network drives. The per-user entry is never used.

NoDriveTypeAutoRun.

This Registry entry disables or enables the AutoRun feature on all drives of the type specified. It reflects the setting of the relevant Autoplay Group Policy. Valid data ranges from 0x00 to 0xFF in hexadecimal notation. If the entry is not present, the default data value is either 0x95 or 0x91 depending on the version of Windows used. An entry present in HKLM overrides any entry present in HKCU.  The entry data is a bitmapped value, where a bit set to 1 disables AutoRun on a particular type of drive. The bit settings for each type of drive are shown below:  Note that bit number 1 is unused and that the "Unknown" type is represented twice. Setting all bits to 1 would give a hexadecimal value of 0xFF, decimal 255, and would disable AutoRun on all types of drives.  The default setting for this entry depends on the version of Windows being used:

NoDriveAutoRun.

This Registry entry disables or enables the AutoRun feature on individual drives. It is not associated with a Group Policy and does not exist by default. The data value is taken to be 0 if the entry is not present. An entry present in HKLM overrides any entry present in HKCU.  The data is a 32 bit (DWORD) bitmapped value, of which the lower 26 bits are used to represent each of the 26 drive letters from A to Z. Thus the valid data range is from 0x0 to 0x03FFFFFF. The least significant bit (the right most bit) represents drive A, and the 26th bit from the right represents drive Z.  A bit set to 1 disables AutoRun on a particular drive. For example, if the data value is set to 0x8 (1000 binary), AutoRun is disabled on drive D.

Group Policy.

The only Group Policy settings available for AutoRun affect the Registry entries. The policy is available on either a per-machine or a per-user basis reflecting the Registry entry location in either HKLM or HKCU. As described above, a per-machine policy setting will cause the per-user policy setting to be ignored.  When a policy is "Enabled", Group Policy will add the entry to the Registry. If the policy is "Disabled" or set to "Not configured", Group Policy deletes this entry from the Registry for the Machine policy (in HKLM) and sets it back to system defaults value for the User policy (in HKCU). System defaults may then take effect as described in the NoDriveTypeAutoRun section.  The policy names, locations and possible settings vary slightly between Windows versions. The list of settings are relatively short and are always additional to the system default setting. Therefore, on Windows 2000, enabling the "Disable Autoplay" policy and setting it to "CD-ROM drives", disables AutoRun (as distinct from AutoPlay) for CD-ROM and DVD drives, removable drives, network drives, and drives of unknown type.  This setting cannot be used to enable AutoRun on drives on which it is disabled by default or disable AutoRun for drives not listed. To disable or enable any particular drives or drive types, the Registry must be edited manually.

Windows Server 2003, Windows XP, and Windows 2000.

The per-machine policy location is:  The per-user policy location is:  The relevant policy is "Turn off Autoplay". In Windows 2000 the policy is called "Disable Autoplay" instead.  Once the policy is Enabled it can be set to "All drives" or "CD-ROM drives". The latter setting adds CD-ROM drives to the existing list of disabled drive types as described above.

Windows Vista, Windows Server 2008.

The per-machine policy location is:  The per-user policy location is:  The relevant policy is "Turn off Autoplay" and can be set for CD-ROM, DVD-ROM and removable drives or all drives.  Two related policies were added in Vista and Server 2008:

Windows 7, Windows Server 2008 R2.

In these versions of Windows, the ability of an autorun.inf file to set an AutoRun task, alter double-click behaviour or change context menus is restricted to drives of type DRIVE_CDROM. There are no policy settings that will override this behaviour. Policy locations and settings are as per "Windows Vista, Windows Server 2008" above with the addition of:

Altering AutoRun behaviour.

Pressing the Shift key.

If the key is held down at a certain point in the execution sequence, Windows Vista invokes the AutoPlay dialog regardless of any AutoPlay settings to the contrary. Previous versions of Windows do not execute the AutoRun task. It is essential that the "left" Shift key is used for this purpose as holding down the right Shift key for eight seconds invokes FilterKeys.  Given that Shift must be held down until Windows checks for it, it may be a considerable amount of time before it becomes effective. The time taken primarily depends on the time to recognise the new hardware and the time taken for CD-ROMs to spin up. It is unsafe to rely on this method.

Auto Insert Notification.

Certain Media Change Notification events may be suppressed by altering certain Registry entries. "Media Change Notification" is the generic term; for CD-ROM drives, the specific term is "Auto Insert Notification".  For CD-ROM drives, changing the value of this Registry entry to 0 will disable Auto Insert Notification for CD-ROM drives only. A Windows restart will be necessary.  Under Windows 95/98/ME, this setting can be changed under Device Manager, accessible from the System icon in Control Panel.  Although the Registry entry is named "AutoRun", it only suppresses the MCN message. The MCN message does trigger AutoRun initiation but it also instructs the Explorer shell to update its views and contents.  Thus, as a side effect only, this disables AutoRun for CD-ROM drives. However, Explorer will now not update its view when a new CD is inserted; it will show the contents of the previous CD until is pressed or View/Refresh is selected from the Explorer menu. This could result in severe confusion for users.  For this reason the Media Change Notification message should not be disabled unless there is absolutely no alternative; AutoRun can be disabled for individual drives using Group Policy or the Registry.  This entry is used to suppress the MCN message for specifically listed type of CD-ROM drive, primarily CD-ROM changers. The data is a set of device identifiers, which matches those identifiers reported to the system by the devices themselves.  The default value for this entry consists of products identified by Microsoft testing as being unable to support AutoRun. This entry should not be altered from its default.

Editing Group Policy.

AutoRun may be suppressed on particular drives and drive types by using the methods described in the Group Policy section. However, the Group Policy Editor is not available on Home versions of Windows XP and does not provide any fine-grained drive selection facilities.  However, Group Policy would be the accepted method of disabling AutoRun on an entire Windows domain.

Registry files.

A Registry setting file can be created that, when executed, makes the desired changes in the Registry.  In the above example, AutoRun would be disabled for all drives and for all users. This example would need to be run as Administrator and a reboot would be needed for the setting to take complete effect.

Initialization file mapping.

Windows Vista and later versions of Windows have a policy setting, "Default behavior for AutoRun", that can be set to disallow the reading of an autorun.inf file on any volume. This avoids certain scenarios where malware leverages autorun.inf functionality to infect a machine. Previous versions of Windows do not have this policy setting but the use of initialisation file mapping is an effective workaround.  As an autorun.inf file is a standard Windows INI file, the appropriate API calls are used by Windows when fetching its settings. These API calls can be redirected using the INI file mapping method. The following Registry file illustrates the workaround, where all autorun.inf settings are taken solely from the Registry key:  As this key does not exist, it is as if the autorun.inf file contains no settings information. It is important to note that this applies to any autorun.inf in any location and on any drive.  Since either the policy setting or this workaround disable autorun, installation of software from an autorunning install CD or DVD will obviously no longer be automatic. It will be necessary to view the CD's autorun.inf file and then execute the appropriate install program manually.

Issues and security.

Microsoft recognized that "Because code may be executed without user's knowledge or consent, users may want to disable this feature because of security concerns." and released a "Fixit" to disable AutoRun for users not comfortable with editing the registry.

The AutoRun disable bug.

From Windows 2000 through to Windows Server 2008, AutoRun-relevant Registry entries were not handled properly leading to a security vulnerability. Windows 95 and Windows 98 were not affected.  When AutoRun is disabled, Windows should not proceed further through the activation sequence than the Registry check. However, it parses any autorun.inf found and does everything except the final action to invoke AutoPlay or execute an application.  This leaves the user open to attack from malware which uses the autorun.inf to alter the double-click and contextual menu behaviours. Double clicking the drive icon will infect the machine. Right Clicking and selecting the "Explore" or "Open" options from the context menu is not a workaround as these menu items can be coopted by the appropriate autorun.inf entries.  This bug was fixed in a number of security updates, detailed in Microsoft Knowledge Base article 967715.

Attack vectors.

AutoRun functionality has been used as a malware vector for some time. Prior to Windows Vista, the default action with a CD-ROM drive type was to follow any autorun.inf file instructions without prompts or warnings. This makes rogue CD-ROMs one possible infection vector.  In the same category are mixed content CD-ROMs. An audio CD, that a user would not expect to contain software at all, can contain a data section with an autorun.inf. Some companies, such as Sony BMG, have used this vector to install malware that attempts to protect against copying of the audio tracks.  U3 enabled flash drives, by emulating a CD-ROM unit, can also cause Windows to execute commands from the autorun.inf found on the emulated CD-ROM.  Devices like the Huawei E220 HSDPA modem validly use this method to autoinstall drivers for the modem itself. However, plugging in a flash drive from an unknown source is an unwise move. USB Switchblade and similar tools have made U3 flash drive attacks trivial. Given the ease of writing script based attacks, anti-virus software may be ineffective in preventing data and password stealing.  With a standard flash drive, social engineering attacks can be employed to entice a user to click on the appropriate item in the AutoPlay dialog. An alluring action string promising free games or pornography would lure many users into the trap. At any time, double clicking on the drive icon will use the autorun.inf automatically, a trap more advanced users could fall into.  Any user can configure AutoPlay to make various decisions for them; by checking the appropriate box in the AutoPlay dialog, running flash drive malware becomes silent and automatic.  AutoRun malware has been extended to use hard drives, picture frames and other digital devices. Care in dealing with external devices is a security priority. The prevalence of malware infection by means of AutoRun and USB flash drive was documented in a 2011 Microsoft study analyzing data from more than 600 million systems worldwide in the first half of 2011. The study found that 26 percent of all malware infections of Windows system were due to USB flash drives exploiting the AutoRun feature in Microsoft Windows. That finding was in line with other statistics, such as the monthly reporting of most commonly detected malware by antivirus company ESET, which lists abuse of autorun.inf as first among the top ten threats in 2011.

Attack mitigation.

In addition to basic security precautions, which include exposure to these attacks can be minimised through the appropriate use of Group Policy and Registry settings. The following security policies are a summary of those described within this article:  In addition, the following actions have been recommended by Microsoft, primarily during the Conficker worm attacks:

AutoRun and the companion feature AutoPlay are components of the Microsoft Windows operating system that dictate what actions the system takes when a drive is mounted.

AutoRun和AutoPlay是微软视窗系统的元件,其内容标示着系统在搜寻到装置时可采取的行动。


Geography.

According to the U.S. Census Bureau, the county has a total area of, of which is land and (9.5%) is water. It is the second-largest county in Maine by area. The largest lake in the county is Moosehead Lake at. The highest natural point in the county and the state of Maine is Mount Katahdin at 5,271 feet (1,606 meters), while the geographic center is Greeley Landing in the Town of Dover-Foxcroft.

Demographics.

2000 census.

As of the 2000 census, there were 17,235 people, 7,278 households, and 4,854 families residing in the county. The population density was 4 people per square mile (2/km2). There were 13,783 housing units at an average density of 4 per square mile (1/km2). The racial makeup of the county was 97.84% White, 0.21% Black or African American, 0.52% Native American, 0.27% Asian, 0.02% Pacific Islander, 0.14% from other races, and 1.00% from two or more races. 0.52% of the population were Hispanic or Latino of any race. 23.6% were of English, 16.4% French, 15.3% United States or American and 11.5% Irish ancestry according to Census 2000. 96.9% spoke English and 2.0% French as their first language.  There were 7,278 households out of which 28.60% had children under the age of 18 living with them, 54.10% were married couples living together, 8.40% had a female householder with no husband present, and 33.30% were non-families. 27.80% of all households were made up of individuals and 14.00% had someone living alone who was 65 years of age or older. The average household size was 2.34 and the average family size was 2.83.  In the county, the population was spread out with 23.40% under the age of 18, 5.70% from 18 to 24, 26.00% from 25 to 44, 27.50% from 45 to 64, and 17.40% who were 65 years of age or older. The median age was 42 years. For every 100 females there were 96.40 males. For every 100 females age 18 and over, there were 95.20 males.  The median income for a household in the county was $28,250, and the median income for a family was $34,852. Males had a median income of $28,149 versus $20,241 for females. The per capita income for the county was $14,374. About 11.20% of families and 14.80% of the population were below the poverty line, including 17.80% of those under age 18 and 13.90% of those age 65 or over.

2010 census.

As of the 2010 United States Census, there were 17,535 people, 7,825 households, and 4,948 families residing in the county. The population density was. There were 15,340 housing units at an average density of. The racial makeup of the county was 96.9% white, 0.7% Asian, 0.5% American Indian, 0.3% black or African American, 0.3% from other races, and 1.2% from two or more races. Those of Hispanic or Latino origin made up 1.0% of the population. In terms of ancestry, 21.4% were English, 16.5% were Irish, 13.6% were American, 8.7% were German, 5.5% were Scottish, and 5.3% were French Canadian.  Of the 7,825 households, 23.6% had children under the age of 18 living with them, 50.1% were married couples living together, 8.5% had a female householder with no husband present, 36.8% were non-families, and 30.5% of all households were made up of individuals. The average household size was 2.21 and the average family size was 2.70. The median age was 48.1 years.  The median income for a household in the county was $34,016 and the median income for a family was $43,821. Males had a median income of $34,575 versus $28,014 for females. The per capita income for the county was $19,870. About 12.3% of families and 16.2% of the population were below the poverty line, including 24.9% of those under age 18 and 12.6% of those age 65 or over.

Religion.

Piscataquis County has one of the lowest rates of religious adherents in the United States. The county ranks at 3,085 of 3,148 counties (lowest 2%), with 20.5% of the population regularly attending congregations or claiming religious membership.  In Maine, Piscataquis County ranks tenth of the 16 counties in percentage of religious adherents. The State of Maine has the lowest percentage of religious adherents in the United States at 27%.

Government and politics.

County officials.

The following individuals hold county offices:

County Commissioners and Districts.

Piscataquis County is administered by three County Commissioners, each representing one of the three county districts. They are elected for four-year terms. A term of office begins on January 1 following the election in November. County Commissioner meetings are typically held on the 1st and 3rd Tuesdays of the month at the County Courthouse in Dover-Foxcroft. The meetings begin at 8:30 a.m. and continue until the agenda for the meeting has been addressed.  County Commissioners:  District 1:Eric P. Ward  District 2:James D. Annis  District 3:Frederick Trask  County Districts:  District 1 includes the towns of Abbot, Beaver Cove, Greenville, Guilford, Kingsbury Plt, Monson, Parkman, Shirley, Wellington and the Unorganized Territories of Blanchard, Elliotsville and Northwest Piscataquis.  District 2 includes the towns of Dover-Foxcroft, Sangerville and Willimantic.  District 3 includes the towns of Bowerbank, Brownville, Lake View Plt, Medford, Milo, Sebec and the Unorganized Territories of Atkinson, Barnard, Ebeeme, Katahdin Iron Works, Orneville, Williamsburg and Northeast Piscataquis County.

Elections.

County Commissioner.

In the 2012 Piscataquis County Commissioner District 2 election, Republican candidate James Annis received 52% of the vote. Democratic candidate Susan Mackey-Andrews received 48%. In the District 3 election, Republican incumbent Frederick Trask received 50.2% (1,282 votes) and Democratic candidate Donald Crossman received 49.8% (1,271 votes) – a difference of 11 votes, confirmed after a recount.

Governor.

In the Maine gubernatorial election, 2010, Republican candidate Paul LePage received the most votes in Piscataquis County with 48.4%. Three Independent candidates ran in this election: Eliot Cutler received the second most Piscatquis votes with 36.5% of the total, Shawn Moody received 3.1% and Kevin Scott, 1%. Democratic candidate, Libby Mitchell received the third most votes in the county with 10.9% of the total. Paul LePage was elected governor.  In the Maine gubernatorial election, 2006, Republican candidate Chandler Woodcock received the most votes in Piscataquis County with 37.7%. Democratic candidate, incumbent governor John Baldacci received 34.5%. Independent candidate Barbara Merrill received 19.7%, Green party candidate Pat LaMarche received 7.4%, and Phillip Morris NaPier received.63% of the Piscataquis vote. John Baldacci was reelected governor.  In the Maine gubernatorial election, 2002, Democratic candidate John Baldacci received the most votes in Piscataquis County with 50.4%. Republican candidate Peter Cianchette received 42.9% of the county vote and Green Party candidate, Jonathan Carter received 5.1%. John Baldacci was elected governor.  In the Maine gubernatorial election, 1998, Independent candidate Angus King received the most votes in Piscataquis County with 50.2%. Republican candidate James Longley, Jr. received 26.6%, Democratic candidate Tom Connolly received 10.7%. Other candidates split 12.5% of the vote. Angus King was elected governor.

US House.

Piscataquis County is entirely within Maine's 2nd congressional district, which comprises 80% of the state and is the largest district by land area east of the Mississippi River.  In the United States House of Representatives elections in Maine, 2012, incumbent Democratic candidate Michael Michaud received the most Piscataquis County votes with 53% of the total. Republican candidate, Kevin Raye received 47%. Michael Michaud was reelected to the House.

US Senate.

In the United States Senate election in Maine, 2012, Independent candidate and former Maine governor, Angus King received the most votes in Piscataquis County with 45.7% of the vote. Republican candidate, Charlie Summers received 40.1% and Democratic candidate Cynthia Dill received 10.4%. Stephen M. Woods received 136 votes, Andrew I. Dodge received 126 votes and Danny F. Dalton, 76 votes. Angus King was elected to the Senate.

President.

In the 2012 United States presidential election, Republican candidate Mitt Romney received the most votes in Piscataquis County with 50.6%. Democratic incumbent Barack Obama received 46.3%. Libertarian candidate Gary Johnson received 1.5% and Green Independent candidate Jill Stein received 1.24%. There were a total of 30 "write in" votes; 29 of these were for Ron Paul and 1 for Rocky Anderson. Barack Obama was reelected President.  Since 2000, Piscataquis County has generally been the most reliably Republican county in Maine, and New England. In 2008, Piscataquis was the only county in New England to vote for John McCain, by a margin of 355 votes or 3.8% over Barack Obama, with Obama winning Maine by a 17.3% margin over McCain. In 2012, Piscataquis was only one of 5 counties in New England to support Republican candidate Mitt Romney.  In 2004, the county was one of only two in Maine to vote for Bush over John Kerry. Bush won by a 9% margin over Kerry, with Kerry winning the state by a virtually even margin over Bush.  In the 2000 U.S. Presidential election, George W. Bush carried the county by an 11.9% margin over Al Gore, with Gore carrying the state by a 5.1% margin over Bush.  In 1996, Bill Clinton carried the county with 48.7% of the vote, the first Democrat to do so since 1968.  In the 1992 presidential election, independent Ross Perot won a plurality 36.8% in the county, one of three counties he won in the state.

Piscataquis County is a county located in the U.S. state of Maine. As of the 2010 census, its population was 17,535, making it Maine's least-populous county. Its county seat is Dover-Foxcroft. The county was incorporated on 23 March 1838, taken from the western part of Penobscot County and the eastern part of Somerset County, and is named for an Abenaki word meaning "branch of the river" or "at the river branch."

孟莫斯郡(英语:Monmouth County)是美国新泽西州东部的一个郡,东临大西洋,北隔拉瑞腾湾与纽约市布鲁克林区及史泰登岛相望,属于纽约大都会区的范围,面积1,723平方公里。根据美国2000年人口普查,共有人口615,301人。郡治为菲力荷自治市 。


Methods of preparation.

Sausage.

Blood sausage is any sausage made by cooking animal blood with a filler until it is thick enough to congeal when cooled. Pig or cattle blood is most often used. Typical fillers include meat, fat, suet, bread, rice, barley and oatmeal. Varieties include biroldo, black pudding, blood tongue, blutwurst, drisheen, kishka (kaszanka), morcilla, moronga, mustamakkara, sundae, verivorst, and many types of boudin.

Pancakes.

Blood pancakes are encountered in Galicia (filloas), Scandinavia, and the Baltic; for example, Swedish blodplättar, Finnish veriohukainen, and Estonian veripannkoogid.

Soups, stews and sauces.

Blood soups and stews, which use blood as part of the broth, include czernina, dinuguan, haejangguk, mykyrokka, pig's organ soup, tiet canh and svartsoppa.  Blood is also used as a thickener in sauces, such as coq au vin or pressed duck, and puddings, such as tiết canh. It can provide flavor or color for meat, as in cabidela.

Solidified.

Blood can also be used as a solid ingredient, either by allowing it to congeal before use, or by cooking it to accelerate the process. Blood curd is a dish typically found in Asia that consists of cooled and hardened animal blood.  In China, "blood tofu" () is most often made with pig's or duck's blood, although chicken's or cow's blood may also be used. The blood is allowed to congeal and simply cut into rectangular pieces and cooked. This dish is also known in Java as "saren", made with chicken's or pig's blood. Blood tofu is found in curry mee as well as the Sichuan dish, Mao Xue Wang. Chinese people use pig blood, tofu, and vegetables to make a healthy soup. Pig blood is rich in vitamin B2, vitamin C, protein, iron, phosphorus, calcium, niacin and other nutrients, while tofu is good for the liver and stomach, and therefore this soup has a reputation as a healthy and tasty meal in China.  In Hungary when a pig is slaughtered in the morning, the blood is fried with onions and served for breakfast.  In Korea, blood curd is typically made of cattle blood and is often used as an ingredient for different kinds of soups and stews, such as hangover soup.  In Tibet, congealed yak's blood is a traditional food.  In Vietnamese cuisine pig blood curd is used in soup based noodles dishes such as Bún bò Huế or Bánh canh.

Raw.

In some cases, blood is used as an ingredient without any additional preparation. Raw blood is not commonly consumed by itself, but may be used as an addition to drinks or other dishes. One example is the drinking of seal blood which is traditionally believed by the Inuit to bring health benefits.

Nutrition bars.

The USSR and ex-USSR countries produce sweet nutrition bars containing cattle blood, known under the generic name Hematogen; originally created for treating anemia, they are also used like regular sweets nowadays.

Religious consumption of blood.

The Catholic Church, as well as the Eastern Orthodox, Oriental Orthodox, and some Anglican churches, believe that in the sacrament of the Eucharist, the participants consume the real blood and body of Jesus Christ. The post-communion prayer of the 1662 Anglican Book of Common Prayer describes the meal as "spiritual food". Many other Christian denominations symbolically consume the Eucharist.  However, nowhere in Christianity is the drink consumed at the Eucharist actual blood, even among denominations believing in transsubstantiation (the sacramental transformation of the bread and wine into the Body and Blood). The liquid consumed is typically wine or grape juice. The consumption of actual blood is in fact forbidden according to the book of Leviticus, part of both Jewish and Christian holy scriptures. The "words of institution", which includes the words Jesus said to his Disciples at the Last Supper, would have been surprising and even unsettling to those present for this reason, especially as the Last Supper was a Passover seder. The ban on consumption of blood by Christians was affirmed after Jesus' death by the Apostolic Decree, chronicled in the Acts of the Apostles.

Cultural considerations.

Some cultures consider blood to be a taboo form of food. In Abrahamic religions, Jewish and Muslim cultures forbid the consumption of blood. Blood and its by-products are forbidden in Islam, in the Qurʼan, surah 5, al-Maʼidah, verse 3. In the New Testament, blood was forbidden by the Apostolic Decree () and is still forbidden among Greek Orthodox. See also Biblical law in Christianity and Communion (Christian).  The Igbo ethnic group of Nigeria has no explicit prohibitions against eating blood, but most regard it with disgust and refuse to eat any meat perceived as "bloody" or undercooked (such as raw meat in sushi or steak prepared raw, rare, or medium). Goats, cattle, and other animals slaughtered in the traditional Igbo manner are dispatched with a single cut across the neck and then most or all of the blood is allowed to slowly drain from the wound. This practice may have been influenced by the Igbo Jewish community that apparently predates contact with Europe. Many Igbos who buy butchered, packaged meat from groceries and supermarkets are in the habit of washing the blood from the meat with water before preparing it.  The taboos may be rooted in the fact that consuming greater quantities of blood is actually poisonous.

Dishes.

Africa.

Among the Maasai people, drinking blood from cattle is a part of the traditional diet, especially after special occasions such as ritual circumcision or the birth of a child.

Americas.

As in Europe, several varieties of blood sausage are also popular in Mexico and the southwest United States (moronga), Peru (relleno), Chile (prietas, ñache), Argentina, Uruguay, Cuba, and Puerto Rico (morcilla).

Brazil.

In Brazil, the traditional Portuguese dish known as cabidela (see above) is also eaten, as well a stew made of pork blood and offal called sarapatel. Chouriço is a blood sausage also eaten in Brazil, known as morcilla in Spanish.

Colombia.

In the western region of Santander Colombia, a dish called pepitoria is made from rice cooked in goat blood. Mexicans from certain regions eat goat's stomach stuffed with pork blood and vegetables as a delicacy.

Ecuador.

Yaguarlocro is a potato soup made with sprinklings of goat's blood.

Asia.

China and Taiwan.

In China and some regions of Southeast Asia, coagulated chicken, duck, goose or pig blood, known in Chinese as "blood tofu" () is used in soups. In Taiwan, "pig's blood cake" () is made of pork blood and sticky rice. It is fried or steamed as a snack or cooked in a hot pot.

India.

In the South Indian state of Tamil Nadu, stir-fried lamb blood is a common dish had for breakfast and lunch. When prepared alone it is called raththam poriyal. More commonly it is stir-fried with lamb stomach and intestines with spices like ginger, garlic, cloves, cinnamon, red chili powder, green chilies, coriander powder, cumin, shallots and grated coconut. This dish is very common in the Madurai and Kongu Nadu region of Tamil Nadu.  In the coastal Konkan region of India, Sorpotel, a dish of Portuguese origin is commonly cooked that includes parboiled meat and offal which is cooked in a spicy and vinegary sauce. Some people also use the animals' blood for boiling the curry. Sorpotel is primarily made by Catholics of Goa, Mangalore and East Indians of Mumbai.

Indonesia.

In Indonesia, especially the Batak tribe in North Sumatera, pig's blood is used as an ingredient and sauce mixed with andaliman ("Zanthoxylum acantophodium") for a cuisine named Sangsang (read saksang). During the Indonesian mass killings of 1965-1966 certain death squad members drank the blood of their victims as they believed it would prevent them from going crazy.

Korea.

In Korea, blood as food is known as "seonji" ( ; derived from the Manchu word "senggi" () meaning "blood"). Coagulated cattle "seonji" and dried radish greens are added to the beef legbone broth in order to make "seonji-guk" (blood curd soup). "Sundae", a blood sausage made generally by boiling or steaming cow or pig's intestines that are stuffed with various ingredients, such as pig's blood, cellophane noodles, kimchi, scallions, etc.

Nepal.

In northern region of Nepal, "Gyuma" a blood sausage is a popular dish commonly eaten by locals. It is made up on Yak's blood and meat. The fillings also include buck wheat flour and other spices. The sausage is also used in lentils or prepared in stir fry dishes.  People of Newari community also consume popular dish called “hee” which means blood which is prepared by steaming the blood with some local spices. It is consumed by most of the locals in Patan, kathmandu area of Nepal.

Philippines.

In the Philippines, a popular dish called "dinuguan" is made from pig's blood and offal seasoned with chili and is traditionally eaten with white rice or steamed rice cakes ("puto"). Numerous variants exist throughout the islands. Dinuguan can also be served without using any offal, using only choice cuts of pork. In Batangas, this version is known as "sinungaok". It can also be made from beef and chicken meat, the latter being known as "dinuguang manok" ('chicken dinuguan'). The Northern Luzon versions of the dish namely the Ilocano "dinardaraan" and the Ibanag "zinagan" are often drier with toppings of deep-fried pork intestine cracklings. These versions are sometimes known as "crispy dinuguan" elsewhere. The Itawis of Cagayan also have a pork-based version that has larger meat chunks and more fat, which they call "twik".  Aside from "dinuguan", a native blood sausage known as "pinuneg" also exists among the Kankanaey people of the highlands of Luzon. Cubes of pork blood grilled on skewers is also a common street food throughout the Philippines. These are known colloquially as "betamax" (after its resemblance to Betamax tapes).  The Ilocano crispy pork dish "bagnet" may also sometimes be dipped in raw pig's blood. Though this is rare. In Western Visayas, the meat-and-liver stew "bas-uy" can also be enriched with blood.

Thailand and Laos.

Coagulated chicken, duck, goose or pig blood is used in soups, such as the classic Thai dish "Tom Lued Moo" (pork blood soup). Thailand also has a dish known as "Nam Tok", which is a spicy soup stock enriched with raw cow or pig's blood. It is often used to enrich regular noodle dishes, as well as in Khao soi.  In Laos and Northeast Thailand), a raw version of "laap", a meat salad, is made with minced raw meat, seasoned in spices, and covered with blood. The spicy noodle soup Nam ngiao and certain variants of Khao soi of the cuisine of Shan State and Northern Thailand contain diced curdled blood.

Vietnam.

In Vietnam, congealed pork blood is used in Bun bo Hue (a spicy noodle soup), as well as congee (a type of rice porridge). It is simply solidified, then put into the broth to absorb the flavor. Blood is also consumed raw in Vietnam although it is not so popular nowadays due to health concern and a better understanding of how raw blood may contain parasites and other organisms that are harmful to human.  This type of raw blood dish is called "tiet canh", literally translated as "blood soup". As its name suggests, the soup is prepared with raw and uncooked animal blood. Firstly, blood is collected when the animal is slaughter, then it is mixed with a little bit of fish sauce or salt water to prevent it from congealing (this step varies a lot from people to people and from region to region), this is to have time to prepare the other part of the dish, usually a mixture of the slaughtered animal's heart, liver, stomach, some time, its kidney, being diced and cooked.  Then, the cooked mixture is divided into serving portions. The blood is now mixed with regular drinking water (there is specific ratio between the blood and the water), then it will be poured onto the cooked mixture. After 10–15 minutes, the blood will start to congeal and the final product will have a consistency similar to jelly. Various herbs, roasted and smashed peanut are topped on the congealed blood to enhance its flavor.  This dish is usually made with pig's blood and duck's blood but it can also be made from any type of animal's blood.  In China and Vietnam certain types of snake blood are considered to be an aphrodisiac, and are drunk with rice wine.

Europe.

Finland.

In Finland, pig's blood is used, with milk, flour and molasses, to make blood pancakes veriohukainen, usually served with lingonberry jam. Also different style of sausages are common, mustamakkara and ryynimakkara. In Åland and Bothnia region is also mustaleipä or verileipä that are bread where liquid of the batter either totally or partially blood. Blackpudding veripalttu is available is some parts of the country.

Germany.

In Northern Germany pig's blood used to be traditionally mixed with vinegar, scraps, spices and sugar to make schwarzsauer. It's eaten warm or preserved in jars. Changes in taste and lifestyle have made this an uncommon dish.

Greece.

In ancient Lakedaimon, the Greek city-state of Sparta, the black broth was common: a soup with pork meat and blood.

Hungary.

In Hungary, "hagymás vér" (pan-fried pig's blood with onions) and "véres hurka" (a kind of blood sausage made with pig's blood, bacon, pork, rice, onion, salt and various herbs and spices) are common winter foods.

Italy.

In Italy, the sanguinaccio dolce is a pudding made with pig blood, chocolate, sugar, pine nuts, raisins and milk.

Portugal.

In Portugal, the northern region known as Minho has a traditional blood soup named papas de sarrabulho. "Papas" translates as "mash" and "sarrabulho" is a popular expression for coagulated blood, so the literal translation would be "mashed blood". The soup is made with pig's blood, chicken meat, pork, ham, salami, lemon and bread, and is typically sprinkled with cumin, which provides the dish with its distinctive odor. It is usually served in the winter because it is a rather heavy dish. The dish is seldom eaten in Southern Portugal. Also very popular, is "morcela" sausage, a type of black pudding. Another traditional Portuguese dish known as cabidela is also made by cooking chicken or rabbit in its own blood, sometimes diluted with vinegar. The same cabidela dish is done with lamprey eel's blood and flesh along with rice, during the months of March and April following the migration of these fishes throughout Portugal's rivers. There's also a sweet done with pig's blood called Papas de moado which is done with flour, sugar, nuts and spices, mainly in the Mondego river region.

Romania.

In Romania there is a traditional sausage prepared with blood names "sângerete", literally meaning "a thing from hemoragy" (it came from "sângera" – "hemoragy" from "sânge" – "blood")), and it is prepared especially during the Ignat (the pig carving holiday).

Spain.

In Spain, the "morcilla" sausage is a kind of black pudding mainly made with pig blood, with spices, fat, and sometimes vegetables. In Andalusia "sangre encebollada" and Valencian "sang amb ceba "are popular dishes made with chicken or pork solidified blood and onion.

Sweden.

In Sweden, the blood soup svartsoppa, made with goose blood, is traditionally eaten on the eve of Saint Martin, especially in the southern region of Skåne. Other popular dishes, with blood as one of the ingredients include blodpudding (blood pudding), blodplättar (blood pancakes), blodpalt (potato dumplings flavoured with reindeer or pig blood) and paltbröd (bread with blood in it, which is dried and boiled and eaten together with fried pork and bèchamel or onion sauce).

United Kingdom and Ireland.

In Britain, Ireland, and some Commonwealth countries, "black pudding" or "blood pudding" is made from blood and some filler grains and spices, often oatmeal. Blood sausage is also popular in Norway (blodpølse), Sweden (blodkorv), Finland (mustamakkara) and Baltic states Latvia (asinsdesa) and Estonia (verivorst), as well as in Poland (kaszanka), Germany (blutwurst), Austria (blunzen), Hungary (véres hurka), Spain (morcilla, botifarra), Croatia (krvavica), Slovakia (krvavnička), Romania (sângerete), Slovenia (krvavica), Ukraine (krovyanka) and France (boudin).  In Montgomeryshire, Wales, goose blood was used to make a pastry tart at Christmas time.  In Ireland, there is ample evidence of the persistence of the practice of bleeding live cattle until well into the 19th century. It was considered to be a preventative measure against cattle diseases, and the blood drawn, when mixed with butter, herbs, oats or meal, provided a nutritious emergency food.

France.

In France, there is "", a solidified/curd blood in a pan. And there is "", a sort of sausage.

Many cultures consume blood as food, often in combination with meat. The blood may be in the form of blood sausage, as a thickener for sauces, a cured salted form for times of food scarcity, or in a blood soup. This is a product from domesticated animals, obtained at a place and time where the blood can run into a container and be swiftly consumed or processed. In many cultures, the animal is slaughtered. In some cultures, blood is a taboo food.

食用血(英语:Blood as food)存在于许多文化之中,它们通常会与肉类食物做搭配结合。食用血也常常被制成血肠,可做为酱汁的增稠剂,以及防腐的盐腌手法,亦可制成汤品。 食用血的来源通常来自于驯养动物,而处理方式,通常是在驯养地或是屠宰场将动物的血管开口,并在第一时间将血液流入容器,使其可以被迅速食用或做进一步处理。由于在多数文化之中,这些驯养动物通常是被宰杀的,因此有些文化之中,血液是一种禁忌食物。


WTI crude oil as a trade grade.

Unlike Brent Crude, WTI crude oil is not associated with any particular crude oil produced from any specific oil fields. Rather, WTI crude oil can be described as "light sweet oil traded and delivered at Cushing, Oklahoma" (with WTI Midland and WTI Houston crude oil defined similarly for Midland, Texas, and Houston, Texas respectively). Historically, local trade between oilfield production and refineries around Midland, Texas and Cushing, Oklahoma could be said to define WTI crude oil, but as local production declined, pipelines into those areas began to deliver other crude oil grades produced and blended elsewhere, which were also accepted as WTI crude oil. The WTI crude oil futures contract formalized this relationship by specifying the deliverable asset for the contract could be blend of crude oil, as long as they are of acceptable lightness and sweetness. Crude oil lightness is characterized by oil gravity, and crude oil sweetness is characterized by Sulfur content. Measurements of lightness and sweetness of WTI changes depending on the particular light and sweet oil traded at Cushing at the time of the measurement, and even the particular measurement methodology. The Platts and Argus API and Sulfur measurements are descriptions of WTI as assessed, while the NYMEX WTI futures contract characterization is a requirement for WTI crude oil delivery to the contract. WTI crude oil will typically satisfy the WTI futures contract requirements and be close to the Platts and Argus assessed values at the time.

Development of the physical WTI market.

The US governmental decontrol of oil prices on January 28, 1981 marked the beginning of the physical WTI Crude Oil spot market. Under the previous US Emergency Petroleum Allocation Act of 1973, WTI crude oil traded under a variety of spot prices split into various categories set by the price controls. After the price decontrol, WTI graded crude oil traded under spot prices centered around spot prices at Cushing, Oklahoma, Midland, Texas, and Houston, Texas (specifically at the Magellan East Houston "MEH" Terminal). Oil price collapses during 1985-1986 significantly reduced local oil production around Cushing, and linked Gulf Coast imported crude oil supplies into the Cushing region and the WTI market. The growth of the WTI spot market came in tandem with the growth of the WTI futures market. The volatility of WTI spot prices lead to the development of WTI futures contracts, while the adoption of the WTI futures contracts as hedging tools by producers and refiners worldwide lead to the worldwide adoption of assessed physical WTI spot prices as benchmark prices for crude.

Global adoption of WTI assessed prices as oil benchmark prices.

Price Reporting Agencies (PRAs), such as Platts and Argus Media, compiled assessment prices of WTI based on prices of spot transactions starting in 1981. Eligible spot transaction prices at Cushing, Oklahoma, is typically reported as WTI, while eligible spot transactions at Midland, Texas, and Houston, Texas (at the MEH Terminal) are reported as WTI Midland, and WTI Houston respectively. The development of WTI spot and futures markets led crude oil producers around the world to use assessed WTI prices as a benchmark in oil pricing. For example, in 2008, Saudi Arabia, Kuwait, Iraq, Colombia, and Ecuador based their crude oil selling prices on either the Platts WTI Mnth 1 index or the Platts WTI Mnth 2 index (the assessed prices of transactions with delivery in the next deliverable month or the second deliverable month). Subsequently, Saudi Arabia, Kuwait, and Iraq started using the Argus Sour Crude Index (ASCI) as their price index in 2009, but the ASCI index itself is priced in relation to WTI futures with a differential, which imply those countries still effectively benchmark their crude oil selling prices to WTI.

NYMEX WTI Crude Oil futures contract.

The volatility of crude oil prices after the US oil price decontrol led to the development of the NYMEX WTI Light Sweet Crude Oil futures contract in 1983. The NYMEX Crude Oil contract trades under the symbol CL on the New York Mercantile Exchange, now part of Chicago Mercantile Exchange. The contract is for 1,000 US barrels, or 42,000 US gallons, of WTI crude oil, the minimum tick size of the contract is $0.01 per barrel ($10 for contract), and the contract price is quoted in US dollars. Monthly contracts are available for the current year, the following 10 calendar years, and 2 additional months. For example, from the perspective of any day in June before the last trade date for the June 2020 contracts, contracts for June 2020, July 2020, August 2020,... December 2030, January 2031, and February 2031 are available for trading. The maximum number of contracts would be 134 contracts, which occurs at the expiry of a December contract when contracts for a new calendar year and two months are made available for trading.

Futures contract delivery.

Cushing, Oklahoma is a major trading hub for crude oil and has been the delivery point for crude contracts and therefore the price settlement point for West Texas Intermediate on the New York Mercantile Exchange for over three decades. The town of Cushing, Oklahoma is a small, remote place with only 7,826 inhabitants (according to the 2010 Census). However, it is the site of the Cushing Oil Field, which was discovered in 1912, and dominated U.S. oil production for several years. The area became a "vital transhipment point with many intersecting pipelines, storage facilities, and easy access to refiners and suppliers," infrastructure which remained after the Cushing field had declined in importance. Crude oil flows "inbound to Cushing from all directions and outbound through dozens of pipelines". It is in Payne County, Oklahoma, United States.

Adoption of WTI futures for investment purposes.

Starting in 2003, an influx of traders from outside of the oil industry begun to participate in oil futures and other commodities futures markets. These market participants, which includes hedge funds, pension funds, insurance companies, and retail investors, were motivated by the increasing acceptance of oil futures contracts and related derivatives as financial assets. Demand from these investors and general financial innovation created inexpensive access to financial instruments related to oil futures contracts, such as options, index funds, and exchange-traded funds. As part of wave of investor interest, WTI crude oil futures prices (as well as Brent Crude oil prices) are included in both the Bloomberg Commodity Index and the S&P GSCI commodity index, which are benchmark indices widely followed in financial markets by traders and institutional investors. Its weighting in these commodity indices give LME Nickel prices non-trivial influence on returns on a wide range of investment funds and portfolios.

Effect of futures contract trading on physical WTI market.

For financial investors without oil storage, purchasing the shortest maturity futures contract and then rolling to the next contract priory to expiry offered the closest approximation to investing in physical oil prices. However, financial markets are much larger than oil markets, and investor flows began to dominate oil producers' hedging needs and moved the oil futures market into contango, where futures prices are greater than spot prices. Contango imposes a roll cost on investors who must roll futures contracts, as they must pay a relatively higher price for those contracts to get the same underlying spot price exposure as their previous expiring contract. These roll costs could be viewed as compensation, purchased virtual storage, or an indirect subsidy for storage owners to provide the service of storing crude on behalf of financial investors. In the WTI context, storage owners would include most participants in the physical WTI market. Beyond the need by financial investors in oil, oil storage is also valuable because it provides insurance against supply disruptions or unexpected increases in demand. Refiners who wish to avoid carrying real physical oil inventories can purchase futures contracts as virtual storage as an alternative. Oil producers wishing to maintain real physical oil inventories similarly could lower the cost of those inventories through selling futures contracts. Index fund participation in the crude oil market is also associated with lower price volatility.  WTI futures contracts are tied to physical deliveries into the physical spot WTI market, so WTI futures contract prices should converge to physical spot WTI market conditions and prices. But since deliveries made to settle an expiring WTI futures contract are also physical spot WTI transactions that can be included into PRA assessed prices, abnormal futures contract transactions could drive WTI spot prices and assessed prices. This was the case on April 20, 2020, when WTI futures contract trading drove both assessed WTI and ASCI prices to negative territories.

WTI Negative Pricing April 20, 2020.

On April 20, 2020, WTI's May contract closed at -$37.63/barrel while the June contract closed at positive $20.43/barrel. Prices mainly dropped due to the COVID-19 pandemic, which reduced demand, with storage issues and the expiration of the May contract on the following day resulting in reduced trading. For the first time ever, the reduction in trading shut down the Trade at Settlement (TAS) mechanism of the May 2020 WTI contract 30 minutes before the end of trading due to a lack of buyers. The TAS shutdown signaled to market participants that all remaining open May 2020 WTI contracts that have to be sold, either outright or for the purposes of rolling to the June 2020 contract, have to be sold in the open market in the next twenty minutes. The speed at which the contracts had to be sold, and the closeness of that time to contract expiry meant that large physical oil traders, who could have transported and stored oil elsewhere given a low enough price, could not buy contracts due to operational, risk management, and position limit constraints. Any remaining traders who were willing to buy contracts gained enormous market power and pushed prices downwards into negative territory. This situation is an extreme case of contango. Assess WTI prices were affected, and the WTI spot price dropped to -$36.98 on April 20th. At the same time, Mars crude oil produced in the US Gulf Coast (USGC) settled at -$26.63, and Middle East exporters who uses ASCI (of which Mars is a component) as the selling price benchmark had to settle for negative prices that day.

Pricing premium/discount in relation to Brent.

Historically, WTI has generally traded at a premium to Brent before 2011, but since the shale oil boom in the 2010s it has been traded at a discounted against Brent crude oil. Both the volatility of the WTI/Brent premium/discount, as well as its reversal from premium to discount in 2011, are studied and monitored by market participants as indicators for the functioning of WTI and Brent Crude as oil price benchmarks.

US supply factors.

In February 2011, WTI was trading around $85/barrel while Brent was at $103/barrel. The reason most cited for this difference was that Cushing had reached capacity due to a surplus of oil in the interior of North America. At the same time, Brent moved up in reaction to civil unrest in Egypt and across the Middle East. Since WTI-priced stockpiles at Cushing could not easily be transported to the Gulf Coast, WTI crude was unable to be arbitraged in bringing the two prices back to parity. Oil prices at coastal areas of the United States were closer to Brent than to WTI. In June 2012, the Seaway Pipeline, which had been transporting oil from the Gulf Coast to Cushing, reversed its flow direction, to transport WTI-priced crude to the Gulf Coast, where it received Brent prices. The price difference persisted, however, and was large enough that some oil producers in North Dakota put their oil on tanker cars, and shipped it by rail to the Gulf and East Coast, where it received Brent prices. Brent continued to trade $10–20 higher than WTI for two years, until June 2013.

Freight rate factors.

To the extent that price difference between WTI and Brent crude entice traders to ship WTI to North Sea refineries or ship Brent to US Gulf Cost refineries, the premium/discount between WTI and Brent crude must reflect oil tanker freight costs. Oil tanker freight cost rates could be highly volatile, due to circular dependence on fuel oil prices and ultimately crude prices, to demand for oil tankers to serve non-USGC non-North-Sea trade routes (especially to China), and to demand for using oil tankers as floating storage for crude oil. From 2000 to 2009, oil tanker freight rates represented a substantial contributor to the WTI premium over Brent crude.

Brent crude production and trading factors.

Premiums/discounts between WTI and Brent crude also reflects declining crude oil production priced under Brent crude prices. As crude production declines from depletion in Brent crude associated North Sea oilfields (Brent, Forties, Oseberg, Ekofisk, and Troll; also referred to as BFOET), a higher proportion of that oil production is consumed by local European refiners, and both a lesser proportion and a lesser absolute amount of that oil production can be exported to the US. During periods when WTI trades at a premium to Brent crude, declining Brent crude production pushes up that premium as traders cannot source supplies to sell into the US for a profit.  As well, participants in the Brent crude market compensates for declining North Sea production by associating additional oilfields and different quality crude production into the definition of Brent crude, which affects the quality differential between Brent and WTI crude oils. Forties and Oseberg crude oil was added in 2002, Ekofisk crude oil was added in 2007, and Troll crude oil was added in 2018 to Brent crude oil pricing basket. Moreover, the different grades in the "Brent basket" are priced different. For example, Ekofisk, Oseberg, and Troll crude oil grades have a quality premium over Brent crude oil grades, while Forties have a price discount for high sulphur content. Brent prices usually reflect the cheapest or the most competitive physical crude oil in the above basket, which means that Brent prices usually reflect prices for Forties crude oil. These quality changes to Brent Crude oil directly affect the premium or discount between what refiners would pay for WTI and Brent crude oil.

West Texas Intermediate (WTI) can refer to a grade or a mix of crude oil, and/or the spot price, the futures price, or the assessed price for that oil; colloquially WTI usually refers to the price of the New York Mercantile Exchange (NYMEX) WTI Crude Oil futures contract or the contract itself. The WTI oil grade is also known as Texas light sweet, although oil produced from any location can be considered WTI if the oil meets required qualifications. Spot and futures prices of WTI are used as a benchmark in oil pricing. This grade is described as light crude oil because of its relatively low density, and sweet because of its low sulfur content.

西得克萨斯中间基原油(英语:West Texas Intermediate,简称英语:WTI)是国际石油市场的一种基准价格,也是纽约商品交易所石油期货合同的标的物。所有在美国生产或销往美国的原油,在计价时都以轻质低硫的WTI作为基准油。


Early life.

Page Joseph Falkinburg, the eldest of three children, was born in Point Pleasant, New Jersey, the son of Sylvia (née Seigel) and Page Falkinburg Sr.  Falkinburg was raised by his father during his early years, after his parents divorced. Page stated that he is of German, Irish, and Dutch origin. Falkinburg/Falkenburg is also the name of multiple German villages and at least three German castles. The name "Dallas" came from his love of the Dallas Cowboys.  His brother, Rory, and sister, Sally, were raised by

Professional wrestling career.

American Wrestling Association (1988).

Falkinburg ran a nightclub in Fort Myers, Florida called "Norma Jeans" (known for its Pink Cadillac) while he was working as a wrestling manager in the American Wrestling Association (AWA). He started managing in 1988, where he handled Badd Company (Paul Diamond and Pat Tanaka), a team he led to

Professional Wrestling Federation (19891991).

Falkinburg also worked as a color commentator in Florida Championship Wrestling (FCW), soon renamed Professional Wrestling Federation (PWF), where he worked alongside Gordon Solie, before finally debuting as a professional wrestler. Falkinburg's first pro match occurred in May 1989 against Dick Slater.  In 1990, Dallas received a tryout with the WWF

World Championship Wrestling/WCW.

Various alliances (1991–1993).

Falkinburg came to World Championship Wrestling (WCW) in 1991 as manager of The Fabulous Freebirds (Jimmy Garvin and Michael P.S. Hayes). Falkinburg managed the Freebirds to a shot at the NWA World Tag Team Championship where they defeated Doom (Butch Reed and Ron Simmons) on February 24. Before that match took place, Falkinburg unveiled the stable's new road manager, Big Daddy Dink, formerly known as Oliver Humperdink, who interfered in the match. During this match, Falkinburg introduced the "Diamond Dolls". Falkinburg added Scott Hall to the stable under the name of Diamond Studd. Falkinburg also worked as a color commentator for WCW with Eric Bischoff. With rumors that the WCW wanted to take the Diamond Studd away from Falkinburg, he decided to take the advice of Magnum T.A. and begin to wrestle himself. He headed to the WCW Power Plant where Buddy Lee Parker, The Assassin, and Dusty Rhodes trained the 35-year-old rookie. He debuted as a wrestler in a tag team match later that year. With the Diamond Studd, he faced Kevin Sullivan and his partner. He was relegated to the "jobber"

World Television Champion and feud with Randy Savage (1994–1997).

Falkinburg, determined to continue improving his character, sought the help of Jake Roberts who advised him on the psychological aspects of the business. After his injury had healed, Falkinburg returned to WCW television in 1994, with his wife Kimberly as the Diamond Doll, and an on-screen bodyguard, Max Muscle. He held open arm wrestling challenges to win Kimberly, but Max always helped him win or arm wrestled for him. He was also involved in an angle where he was said to have supposedly amassed the sum of 13 million dollars through victories in arm wrestling competitions, a fortune that he would later lose. He also had a long feud with Dave Sullivan because Sullivan gave

United States Heavyweight Champion (1997–1998).

At Starrcade, Page won the United States Heavyweight Championship from Curt Hennig. The following year at Uncensored, Page defended the title in a Triple Threat, Falls Count Anywhere contest against Chris Benoit and Raven, putting Raven through a table with a Diamond Cutter to retain the belt. Page later lost the title to Raven at Spring Stampede. Later in the year, Page tagged with Karl Malone against Hulk Hogan and Dennis Rodman at Bash at the Beach, losing due to interference. Page tagged with late night talk show host Jay Leno at Road Wild, where they defeated Hogan and Eric Bischoff.  At Fall Brawl, Page won the WarGames main event, and got a World title shot against

World Heavyweight Champion (1999–2001).

Page became WCW World Heavyweight Champion in April 1999, at Spring Stampede when he defeated Sting, Hogan, and Ric Flair for the title in a Four Way Dance with "Macho Man" Randy Savage as Special Guest Referee. Page pinned Flair after giving Flair the Diamond Cutter. Around this time some fans were starting to boo Page at various WCW events, so shortly after Spring Stampede a decision was made to turn Page heel for the first time in three years. The turn played out slowly at first, with Page undergoing a change in attitude. Then, on April 19, Page defended his title against Goldberg, where he cemented the then by first knocking Goldberg out with brass knuckles and then propping his leg up against the ring stairs and repeatedly smashing it with a steel chair, all while taunting the fans with repeated utterances of "boo me now". Page only stopped when Kevin Nash, an ally of Hogan's who was angry at Page for (kayfabe) injuring Hogan's knee during the match at Spring Stampede, came back from injury and chased him away.  On April 26, 1999, Page lost and regained his title in the span of two hours. Sting challenged him to defend his title in the first hour of that night's "Nitro" and defeated him to regain the title he had lost a year earlier. This ended Page's reign at 15 days, but he gained an opportunity to get the title back ninety minutes later. Nash came to the ring and made a challenge for a four-way match for the title, and the just-dethroned Page joined defending champion Sting and Goldberg in the match. Page regained the world title by using a foreign object to hit Nash and take the win and regain the title without actually defeating the reigning champion. Nash became the number one contender shortly after and vowed to get revenge on Page for his friend Hogan, culminating in a match at Slamboree in May. Page originally retained the world championship after Savage interfered and hit Nash, but the match was ordered to continue by Eric Bischoff and Nash pinned Page to win the title after a powerbomb. Page dropped

World Wrestling Federation (2001–2002).

When WCW was purchased by WWF owner Vince McMahon in 2001, Page was one of the few major WCW stars (along with Booker T and Buff Bagwell) who accepted buyouts of their AOL Time Warner contracts in order to immediately sign with McMahon. He debuted in the World Wrestling Federation (WWF) on the June 18, 2001 episode of "Raw" when he unveiled himself as the stalker of The Undertaker's wife, Sara. Page revealed he didn't care about Sara; he only did it to make an impact

Return to Wrestling (2004).

In 2004, Page made his in-ring return by wrestling for several independent promotions. His first match

Total Nonstop Action Wrestling (2004–2005).

He signed with Total Nonstop Action Wrestling (TNA). He would debut for the company on the November 12 taping of "Impact!", where he attacked Raven, beginning a feud between the two. At Turning Point on December 5, DDP defeated Raven. and at Final Resolution in January 2005, Page competed in a three-way elimination match to determine the number one contender for the NWA World Heavyweight Championship also involving Monty Brown and Kevin Nash, which was won by Brown. Page and

Independent Circuit (2005–2006).

After TNA, Page returned to the independent circuit. He lost to Larry Zbyszko at WrestleReunion. DDP had Bruno Sammartino in his corner

Juggalo Championship Wrestling (2009).

On August 9, 2009, Diamond Dallas Page made a special appearance for Juggalo Championship

Return to Independent Circuit (2010–2011).

DDP returned to wrestling on January 2, 2010 teaming with Air Paris to defeat Bobby Hayes and Alexander

Return to WWE (2011–2017).

In late 2010, Page agreed to work on a DVD for WWE, titled "The Very Best of WCW Monday Nitro", after being approached on the project due to his ties to WCW. Page hosted the DVD, which was released on June 7, 2011. On the June 27 episode of "Raw", Page made an appearance promoting this DVD with Booker T.  In 2012, Page appeared on WWE Classics on Demand in "Legends of Wrestling Roundtable: Renegades" along with Jim Ross, Michael P.S. Hayes, Roddy Piper, and Gene Okerlund. Page also appeared alongside Kevin Nash and X-Pac at the WWE Hall of Fame ceremony on March 31, 2012. On July

All In (2018).

At All In on September 1, 2018, Page

All Elite Wrestling (2019–present).

On May 25, 2019, during their inaugural pay-per-view Double or Nothing, Page escorted Brandi Rhodes away from the ring after she refused to leave the match between Cody Rhodes and Dustin Rhodes after match referee Earl Hebner ejected her from the match.

Other media.

Page developed a yoga fitness program initially called "Yoga for Regular Guys Workout" or "YRG" after recovering from ruptures to his L4/L5 discs in 1998 and discovering the health benefits of yoga through his former wife, Kimberly. His favorite kind of yoga (according to his "Yoga for Regular Guys" book published in 2005) is "Power Yoga," an American-style version of "Ashtanga Style" yoga. Page worked with Doctor of Chiropractic Dr. Craig Aaron, the "Yoga-Doc" and developed the "Yoga for Regular Guys Workout".  Page developed the book into a series of workout videos titled DDP YOGA (formerly YRG). DDP Yoga was featured in a video about Arthur Boorman in May 2012. The story was picked up by the mainstream media, including "Good Morning America". The video describes the journey of Arthur Boorman, a disabled war veteran who was told by doctors he would never walk again After 15 years on crutches, Boorman followed Page's yoga plan for ten months and documented his progress on home video. Boorman lost 140 pounds and regained the strength and flexibility to walk and run without his crutches, back braces or leg braces.  DDP Yoga hasn't been without its critics: former WCW announcer Mark Madden, who has never gotten along with Page and has often referred to him as "DDMe" on his online articles and his radio shows, noted that Page used TV cameras to film the progress of Jake Roberts and Scott Hall while they were rehabbing in Page's home, which he felt was unnecessary. On February 21, 2014, Page appeared on the ABC series "Shark Tank", where he was seeking $200,200 for a 5% share in the company. He declined to sell a 50% share for that same amount to Kevin O'Leary. Page had hoped to use the money to develop a mobile app. The other investors were impressed by Boorman's improvement but believed the home exercise market was too competitive and also predicted net profits ($800,000 in the previous year) would fall. Page later said he sold more than $1 million worth of product in the first six days after his appearance.  In 2016, Page was featured on the "Nine Legends" Expansion Pack to talk about his friend Bill Goldberg.  Page also hosts a radio show titled "DDP Radio".

Video games.

Page has appeared in

Lawsuits.

Page is commonly associated with the "Self High Five" as well as the "Diamond Cutter" symbol, a hand gesture made by joining the thumbs and index fingers on each hand to form a diamond shape, then parting the two hands in one swift motion. He created the symbol in 1996 and later trademarked it. In December 2005, Page filed a lawsuit against rapper Jay-Z, who, he claimed, had "illegally adopted his trademark hand gesture". Page accused Jay-Z of

Personal life.

Page released his autobiography, "Positively Page: The Diamond Dallas Page Journey", on February 1, 2000.  In 2003, he had his name legally changed to Dallas Page.  On December 1, 1991, Page married Kimberly Page. On July 3, 2004, they announced their amicable separation, before divorcing in 2005.  In an August 2014 "New York Times" article, Page was described as being engaged to a woman named Brenda Nair of Smyrna, Georgia. They married in Cancun on July 25, 2015. Page has two daughters, Brittany Page (born 1987) and Kimberly Page (born 1994), and two stepdaughters, Alexandra Nair (born 1996) and Rachel Nair (born 2001). Alexandra currently works for All Elite Wrestling (AEW) as a backstage interviewer.  On January 15, 2019, Page released another book, "Positively Unstoppable: The Art of Owning It", through Rodale Books. The book includes a foreword by Mick Foley.  On December 18, 2019, Page and his wife Brenda announced they were divorcing. They were separated for 3 months before the announcement.

Dallas Page (born Page Joseph Falkinburg, April 5, 1956), better known by his ring name Diamond Dallas Page (DDP), is an American semi-retired professional wrestler, fitness instructor, motivational speaker, and actor. In the course of his wrestling career, which spanned two decades, Page has wrestled for mainstream wrestling promotions World Championship Wrestling (WCW), the World Wrestling Federation (WWF, now WWE), Total Nonstop Action Wrestling (TNA), and All Elite Wrestling (AEW).

达勒斯·沛莒(英语:Dallas Page,1956年-4月5日),本名小沛莒·约瑟夫·佛克因柏(英语:Page Joseph Falkinburg, Jr.),是美国已退休的职业摔角选手、健身教练及演员。而广为人知的是他的擂台名钻石达勒斯·沛莒。达勒斯·沛莒最出名的时期是担任世界冠军摔角的选手。在达勒斯·沛莒二十余年的职业生涯中,他曾待的主要摔角联盟包括世界冠军摔角、世界摔角联盟及永不停止摔角。


History.

Informal part-whole reasoning was consciously invoked in metaphysics and ontology from Plato (in particular, in the second half of the "Parmenides") and Aristotle onwards, and more or less unwittingly in 19th-century mathematics until the triumph of set theory around 1910.  Ivor Grattan-Guinness (2001) sheds much light on part-whole reasoning during the 19th and early 20th centuries, and reviews how Cantor and Peano devised set theory. It appears that the first to reason consciously and at length about parts and wholes was Edmund Husserl, in 1901, in the second volume of "Logical Investigations" – Third Investigation: "On the Theory of Wholes and Parts" (Husserl 1970 is the English translation). However, the word "mereology" is absent from his writings, and he employed no symbolism even though his doctorate was in mathematics.  Stanisław Leśniewski coined "mereology" in 1927, from the Greek word μέρος ("méros", "part"), to refer to a formal theory of part-whole he devised in a series of highly technical papers published between 1916 and 1931, and translated in Leśniewski (1992). Leśniewski's student Alfred Tarski, in his Appendix E to Woodger (1937) and the paper translated as Tarski (1984), greatly simplified Leśniewski's formalism. Other students (and students of students) of Lesniewski elaborated this "Polish mereology" over the course of the 20th century. For a good selection of the literature on Polish mereology, see Srzednicki and Rickey (1984). For a survey of Polish mereology, see Simons (1987). Since 1980 or so, however, research on Polish mereology has been almost entirely historical in nature.  A. N. Whitehead planned a fourth volume of "Principia Mathematica", on geometry, but never wrote it. His 1914 correspondence with Bertrand Russell reveals that his intended approach to geometry can be seen, with the benefit of hindsight, as mereological in essence. This work culminated in Whitehead (1916) and the mereological systems of Whitehead (1919, 1920).  In 1930, Henry S. Leonard completed a Harvard Ph.D. dissertation in philosophy, setting out a formal theory of the part-whole relation. This evolved into the "calculus of individuals" of Goodman and Leonard (1940). Goodman revised and elaborated this calculus in the three editions of Goodman (1951). The calculus of individuals is the starting point for the post-1970 revival of mereology among logicians, ontologists, and computer scientists, a revival well-surveyed in Simons (1987) and Casati and Varzi (1999).

Axioms and primitive notions.

Reflexivity: A basic choice in defining a mereological system, is whether to consider things to be parts of themselves. In naive set theory a similar question arises: whether a set is to be considered a "subset" of itself. In both cases, "yes" gives rise to paradoxes analogous to Russell's paradox: Let there be an object O such that every object that is not a proper part of itself is a proper part of O. Is O a proper part of itself? No, because no object is a proper part of itself; and yes, because it meets the specified requirement for inclusion as a proper part of O. In set theory, a set is often termed an "improper" subset of itself. Given such paradoxes, mereology requires an axiomatic formulation.  A mereological "system" is a first-order theory (with identity) whose universe of discourse consists of wholes and their respective parts, collectively called "objects". Mereology is a collection of nested and non-nested axiomatic systems, not unlike the case with modal logic.  The treatment, terminology, and hierarchical organization below follow Casati and Varzi (1999: Ch. 3) closely. For a more recent treatment, correcting certain misconceptions, see Hovda (2008). Lower-case letters denote variables ranging over objects. Following each symbolic axiom or definition is the number of the corresponding formula in Casati and Varzi, written in bold.  A mereological system requires at least one primitive binary relation (dyadic predicate). The most conventional choice for such a relation is parthood (also called "inclusion"), ""x" is a "part" of "y"", written "Pxy". Nearly all systems require that parthood partially order the universe. The following defined relations, required for the axioms below, follow immediately from parthood alone: Overlap and Underlap are reflexive, symmetric, and intransitive.  Systems vary in what relations they take as primitive and as defined. For example, in extensional mereologies (defined below), "parthood" can be defined from Overlap as follows:  The axioms are:

Various systems.

Simons (1987), Casati and Varzi (1999) and Hovda (2008) describe many mereological systems whose axioms are taken from the above list. We adopt the boldface nomenclature of Casati and Varzi. The best-known such system is the one called "classical extensional mereology", hereinafter abbreviated CEM (other abbreviations are explained below). In CEM, P.1 through P.8' hold as axioms or are theorems. M9, "Top", and "Bottom" are optional.  The systems in the table below are partially ordered by inclusion, in the sense that, if all the theorems of system A are also theorems of system B, but the converse is not necessarily true, then B "includes" A. The resulting Hasse diagram is similar to Fig. 3.2 in Casati and Varzi (1999: 48).  There are two equivalent ways of asserting that the universe is partially ordered: Assume either M1–M3, or that Proper "Parthood" is transitive and asymmetric, hence a strict partial order. Either axiomatization results in the system M. M2 rules out closed loops formed using "Parthood", so that the part relation is well-founded. Sets are well-founded if the axiom of regularity is assumed. The literature contains occasional philosophical and common-sense objections to the transitivity of "Parthood".  M4 and M5 are two ways of asserting "supplementation", the mereological analog of set complementation, with M5 being stronger because M4 is derivable from M5. M and M4 yield "minimal" mereology, MM. MM, reformulated in terms of Proper Part, is Simons's (1987) preferred minimal system.  In any system in which M5 or M5' are assumed or can be derived, then it can be proved that two objects having the same proper parts are identical. This property is known as "Extensionality", a term borrowed from set theory, for which extensionality is the defining axiom. Mereological systems in which Extensionality holds are termed "extensional", a fact denoted by including the letter E in their symbolic names.  M6 asserts that any two underlapping objects have a unique sum; M7 asserts that any two overlapping objects have a unique product. If the universe is finite or if "Top" is assumed, then the universe is closed under "sum". Universal closure of "Product" and of supplementation relative to "W" requires "Bottom". "W" and "N" are, evidently, the mereological analog of the universal and empty sets, and "Sum" and "Product" are, likewise, the analogs of set-theoretical "union" and "intersection". If M6 and M7 are either assumed or derivable, the result is a mereology with "closure".  Because "Sum" and "Product" are binary operations, M6 and M7 admit the sum and product of only a finite number of objects. The "fusion" axiom, M8, enables taking the sum of infinitely many objects. The same holds for "Product", when defined. At this point, mereology often invokes set theory, but any recourse to set theory is eliminable by replacing a formula with a quantified variable ranging over a universe of sets by a schematic formula with one free variable. The formula comes out true (is satisfied) whenever the name of an object that would be a member of the set (if it existed) replaces the free variable. Hence any axiom with sets can be replaced by an axiom schema with monadic atomic subformulae. M8 and M8' are schemas of just this sort. The syntax of a first-order theory can describe only a denumerable number of sets; hence, only denumerably many sets may be eliminated in this fashion, but this limitation is not binding for the sort of mathematics contemplated here.  If M8 holds, then "W" exists for infinite universes. Hence, "Top" need be assumed only if the universe is infinite and M8 does not hold. "Top" (postulating "W") is not controversial, but "Bottom" (postulating "N") is. Leśniewski rejected "Bottom", and most mereological systems follow his example (an exception is the work of Richard Milton Martin). Hence, while the universe is closed under sum, the product of objects that do not overlap is typically undefined. A system with "W" but not "N" is isomorphic to: Postulating "N" renders all possible products definable, but also transforms classical extensional mereology into a set-free model of Boolean algebra.  If sets are admitted, M8 asserts the existence of the fusion of all members of any nonempty set. Any mereological system in which M8 holds is called "general", and its name includes G. In any general mereology, M6 and M7 are provable. Adding M8 to an extensional mereology results in "general extensional mereology", abbreviated GEM; moreover, the extensionality renders the fusion unique. On the converse, however, if the fusion asserted by M8 is assumed unique, so that M8' replaces M8, then—as Tarski (1929) had shown—M3 and M8' suffice to axiomatize GEM, a remarkably economical result. Simons (1987: 38–41) lists a number of GEM theorems.  M2 and a finite universe necessarily imply "Atomicity", namely that everything either is an atom or includes atoms among its proper parts. If the universe is infinite, "Atomicity" requires M9. Adding M9 to any mereological system, X results in the atomistic variant thereof, denoted AX. "Atomicity" permits economies, for instance, assuming that M5' implies "Atomicity" and extensionality, and yields an alternative axiomatization of AGEM.

Set theory.

The notion of "subset" in set theory is not entirely the same as the notion of "subpart" in mereology. Stanisław Leśniewski rejected set theory as related to but not the same as nominalism. For a long time, nearly all philosophers and mathematicians avoided mereology, seeing it as tantamount to a rejection of set theory. Goodman too was a nominalist, and his fellow nominalist Richard Milton Martin employed a version of the calculus of individuals throughout his career, starting in 1941.  Much early work on mereology was motivated by a suspicion that set theory was ontologically suspect, and that Occam's razor requires that one minimise the number of posits in one's theory of the world and of mathematics. Mereology replaces talk of "sets" of objects with talk of "sums" of objects, objects being no more than the various things that make up wholes.  Many logicians and philosophers reject these motivations, on such grounds as: For a survey of attempts to found mathematics without using set theory, see Burgess and Rosen (1997).  In the 1970s, thanks in part to Eberle (1970), it gradually came to be understood that one can employ mereology regardless of one's ontological stance regarding sets. This understanding is called the "ontological innocence" of mereology. This innocence stems from mereology being formalizable in either of two equivalent ways: Once it became clear that mereology is not tantamount to a denial of set theory, mereology became largely accepted as a useful tool for formal ontology and metaphysics.  In set theory, singletons are "atoms" that have no (non-empty) proper parts; many consider set theory useless or incoherent (not "well-founded") if sets cannot be built up from unit sets. The calculus of individuals was thought to require that an object either have no proper parts, in which case it is an "atom", or be the mereological sum of atoms. Eberle (1970), however, showed how to construct a calculus of individuals lacking "atoms", i.e., one where every object has a "proper part" (defined below) so that the universe is infinite.  There are analogies between the axioms of mereology and those of standard Zermelo–Fraenkel set theory (ZF), if "Parthood" is taken as analogous to subset in set theory. On the relation of mereology and ZF, also see Bunt (1985). One of the very few contemporary set theorists to discuss mereology is Potter (2004).  Lewis (1991) went further, showing informally that mereology, augmented by a few ontological assumptions and plural quantification, and some novel reasoning about singletons, yields a system in which a given individual can be both a member and a subset of another individual. In the resulting system, the axioms of ZFC (and of Peano arithmetic) are theorems.  Forrest (2002) revises Lewis's analysis by first formulating a generalization of CEM, called "Heyting mereology", whose sole nonlogical primitive is "Proper Part", assumed transitive and antireflexive. There exists a "fictitious" null individual that is a proper part of every individual. Two schemas assert that every lattice join exists (lattices are complete) and that meet distributes over join. On this Heyting mereology, Forrest erects a theory of "pseudosets", adequate for all purposes to which sets have been put.

Mathematics.

Husserl never claimed that mathematics could or should be grounded in part-whole rather than set theory. Lesniewski consciously derived his mereology as an alternative to set theory as a foundation of mathematics, but did not work out the details. Goodman and Quine (1947) tried to develop the natural and real numbers using the calculus of individuals, but were mostly unsuccessful; Quine did not reprint that article in his "Selected Logic Papers". In a series of chapters in the books he published in the last decade of his life, Richard Milton Martin set out to do what Goodman and Quine had abandoned 30 years prior. A recurring problem with attempts to ground mathematics in mereology is how to build up the theory of relations while abstaining from set-theoretic definitions of the ordered pair. Martin argued that Eberle's (1970) theory of relational individuals solved this problem.  Topological notions of boundaries and connection can be married to mereology, resulting in mereotopology; see Casati and Varzi (1999: chpts. 4,5). Whitehead's 1929 "Process and Reality" contains a good deal of informal mereotopology.

Natural language.

Bunt (1985), a study of the semantics of natural language, shows how mereology can help understand such phenomena as the mass–count distinction and verb aspect. But Nicolas (2008) argues that a different logical framework, called plural logic, should be used for that purpose. Also, natural language often employs "part of" in ambiguous ways (Simons 1987 discusses this at length). Hence, it is unclear how, if at all, one can translate certain natural language expressions into mereological predicates. Steering clear of such difficulties may require limiting the interpretation of mereology to mathematics and natural science. Casati and Varzi (1999), for example, limit the scope of mereology to physical objects.

Metaphysics.

In metaphysics there are many troubling questions pertaining to parts and wholes. One question addresses constitution and persistence, another asks about composition.

Mereological constitution.

In metaphysics, there are several puzzles concerning cases of mereological constitution. That is, what makes up a whole. We are still concerned with parts and wholes, but instead of looking at what parts make up a whole, we are wondering what a thing is made of, such as its materials: e.g. the bronze in a bronze statue. Below are two of the main puzzles that philosophers use to discuss constitution.  "Ship of Theseus:" Briefly, the puzzle goes something like this. There is a ship called the Ship of Theseus. Over time, the boards start to rot, so we remove the boards and place them in a pile. First question, is the ship made of the new boards the same as the ship that had all the old boards? Second, if we reconstruct a ship using all of the old planks, etc. from the Ship of Theseus, and we also have a ship that was built out of new boards (each added one-by-one over time to replace old decaying boards), which ship is the real Ship of Theseus?  "Statue and Lump of Clay:" Roughly, a sculptor decides to mold a statue out of a lump of clay. At time t1 the sculptor has a lump of clay. After many manipulations at time t2 there is a statue. The question asked is, is the lump of clay and the statue (numerically) identical? If so, how and why?  Constitution typically has implications for views on persistence: how does an object persist over time if any of its parts (materials) change or are removed, as is the case with humans who lose cells, change height, hair color, memories, and yet we are said to be the same person today as we were when we were first born. For example, Ted Sider is the same today as he was when he was born—he just changed. But how can this be if many parts of Ted today did not exist when Ted was just born? Is it possible for things, such as organisms to persist? And if so, how? There are several views that attempt to answer this question. Some of the views are as follows (note, there are several other views):  (a) Constitution view. This view accepts cohabitation. That is, two objects share exactly the same matter. Here, it follows, that there are no temporal parts.  (b) Mereological essentialism, which states that the only objects that exist are quantities of matter, which are things defined by their parts. The object persists if matter is removed (or the form changes); but the object ceases to exist if any matter is destroyed.  (c) Dominant Sorts. This is the view that tracing is determined by which sort is dominant; they reject cohabitation. For example, lump does not equal statue because they're different "sorts".  (d) Nihilism—which makes the claim that no objects exist, except simples, so there is no persistence problem.  (e) 4-dimensionalism or temporal parts (may also go by the names perdurantism or exdurantism), which roughly states that aggregates of temporal parts are intimately related. For example, two roads merging, momentarily and spatially, are still one road, because they share a part.  (f) 3-dimensionalism (may also go by the name endurantism), where the object is wholly present. That is, the persisting object retains numerical identity.

Mereological composition.

One question that is addressed by philosophers is which is more fundamental: parts, wholes, or neither? Another pressing question is called the special composition question (SCQ): For any Xs, when is it the case that there is a Y such that the Xs compose Y? This question has caused philosophers to run in three different directions: nihilism, universal composition (UC), or a moderate view (restricted composition). The first two views are considered extreme since the first denies composition, and the second allows any and all non-spatially overlapping objects to compose another object. The moderate view encompasses several theories that try to make sense of SCQ without saying 'no' to composition or 'yes' to unrestricted composition.

Fundamentality.

There are philosophers who are concerned with the question of fundamentality. That is, which is more ontologically fundamental the parts or their wholes. There are several responses to this question, though one of the default assumptions is that the parts are more fundamental. That is, the whole is grounded in its parts. This is the mainstream view. Another view, explored by Shaffer (2010) is monism, where the parts are grounded in the whole. Shaffer does not just mean that, say, the parts that make up my body are grounded in my body. Rather, Shaffer argues that the whole "cosmos" is more fundamental and everything else is a part of the cosmos. Then, there is the identity theory which claims that there is no hierarchy or fundamentality to parts and wholes. Instead wholes "are just" (or equivalent to) their parts. There can also be a two-object view which says that the wholes are not equal to the parts—they are numerically distinct from one another. Each of these theories has benefits and costs associated with them.

Special composition question (SCQ).

Philosophers want to know when some Xs compose something Y. There are several kinds of responses:  (a) Contact—the Xs compose a complex Y if and only if the Xs are in contact;  (b) Fastenation—the Xs compose a complex Y if and only if the Xs are fastened;  (c) Cohesion—the Xs compose a complex Y if and only if the Xs cohere (cannot be pulled apart or moved in relation to each other without breaking);  (d) Fusion—the Xs compose a complex Y if and only if the Xs are fused (fusion is when the Xs are joined together such that there is no boundary);  (e) Organicism—the Xs compose a complex Y if and only if either the activities of the Xs constitute a life or there is only one of the Xs; and  (f) Brutal Composition—"It's just the way things are." There is no true, nontrivial, and finitely long answer.  This is not an exhaustive list as many more hypotheses continue to be explored. However, a common problem with these theories is that they are vague. It remains unclear what "fastened" or "life" mean, for example. But there are many other issues within the restricted composition responses—though many of them are subject to which theory is being discussed.

Important surveys.

The books by Simons (1987) and Casati and Varzi (1999) differ in their strengths:  Simons devotes considerable effort to elucidating historical notations. The notation of Casati and Varzi is often used. Both books include excellent bibliographies. To these works should be added Hovda (2008), which presents the latest state of the art on the axiomatization of mereology.

In philosophy and mathematical logic, mereology (from the Greek μέρος "meros" (root: μερε- "mere-", "part") and the suffix -logy "study, discussion, science") is the study of parts and the wholes they form. Whereas set theory is founded on the membership relation between a set and its elements, mereology emphasizes the meronomic relation between entities, which—from a set-theoretic perspective—is closer to the concept of inclusion between sets.

在哲学方面,分体论(英文:英语:Mereology;该单词源自希腊语“""”;其中,词头“"meros"”意思是“部分”或者说“组成部分”,而词尾“"-logy"”则指的是研究、学问、讨论和科学),是指一套与组成部分及其相应整体有关的公理化一阶理论。分体论既指的是谓词逻辑的一种应用,又指的是形式本体论的一个分支。