Numinous

Numinous () is a term derived from the Latin "numen", meaning "arousing spiritual or religious emotion; mysterious or awe-inspiring." The term was given its present sense by the German theologian and philosopher Rudolf Otto in his influential 1917 German book "The Idea of the Holy". He also used the phrase mysterium tremendum as another description for the phenomenon. Otto's concept of the numinous influenced thinkers including Carl Jung, Mircea Eliade, and C. S. Lewis. It has been applied to theology, psychology, religious studies, literary analysis, and descriptions of psychedelic experiences.
Etymology.
"Numinous" was derived in the 17th century from the Latin "numen", meaning a "deity or spirit presiding over a thing or space." It describes the power or presence or realisation of a divinity. It is etymologically unrelated to Immanuel Kant's "noumenon", a Greek term referring to an unknowable reality underlying all things.
Rudolf Otto.
The word was given its present sense by the German theologian and philosopher Rudolf Otto in his influential 1917 book "Das Heilige", which appeared in English as "The Idea of the Holy" in 1923. 
Otto writes that while the concept of "the holy" is often used to convey moral perfection—and does entail this—it contains another distinct element, beyond the ethical sphere, for which he uses the term "numinous". He explains the numinous as a "non-rational, non-sensory experience or feeling whose primary and immediate object is outside the self." This mental state "presents itself as "ganz Andere", wholly other, a condition absolutely "sui generis" and incomparable whereby the human being finds himself utterly abashed."
Otto argues that because the numinous is irreducible and "sui generis" it cannot be defined in terms of other concepts or experiences, and that the reader must therefore be "guided and led on by consideration and discussion of the matter through the ways of his own mind, until he reach the point at which 'the numinous' in him perforce begins to stir... In other words, our "X" cannot, strictly speaking, be taught, it can only be evoked, awakened in the mind." Chapters 4 to 6 are devoted to attempting to evoke the numinous and its various aspects.
Using Latin, he describes it as a mystery () that is at once terrifying ("tremendum") and fascinating ("fascinans"). He writes:
Later use of the concept.
Otto's use of the term as referring to a characteristic of religious experience was influential among certain intellectuals of the subsequent generation. For example, "numinous" as understood by Otto was a frequently quoted concept in the writings of Carl Jung, and C. S. Lewis. Lewis described the numinous experience in "The Problem of Pain" as follows:
Jung applied the concept of the numinous to psychology and psychotherapy, arguing it was therapeutic and brought greater self-understanding, and stating that to him religion was about a "careful and scrupulous observation... of the "numinosum"". The notion of the numinous and the "wholly Other" were also central to the religious studies of ethnologist Mircea Eliade. "Mysterium tremendum", another phrase coined by Otto to describe the numinous, is presented by Aldous Huxley in "The Doors of Perception" in this way:
In a book-length scholarly treatment of the subject in fantasy literature, Chris Brawley devotes chapters to the concept in "The Rime of the Ancient Mariner" by Samuel Taylor Coleridge, in "Phantastes" by George Macdonald, in the "Chronicles of Narnia" by C. S. Lewis, and "The Lord of the Rings" by J. R. R. Tolkien; and in work by Algernon Blackwood and Ursula Le Guin (e.g., "The Centaur" and "Buffalo Gals, Won't You Come Out Tonight", respectively).
Neuroscientist Christof Koch has described awe from experiences such as entering a cathedral, saying he gets "a feeling of luminosity out of the numinous," though he does not hold the Catholic religious beliefs with which he was raised.
Psychologist Susan Blackmore describes both mystical experiences and psychedelic experiences as numinous. In 2009, Czech psychiatrist Stanislav Grof re-released his 1975 book "Realms of the Human Unconscious" under the title "LSD: Doorway to the Numinous: The Groundbreaking Psychedelic Research into Realms of the Human Unconscious". In his 2018 book "How to Change Your Mind", journalist Michael Pollan describes his experience trying the powerful psychedelic substance 5-MeO-DMT, including the following reflection on his experience of ego dissolution: