''Idios kosmos'' (from grc, ίδιος κόσμος) is people's "own world" or "private world" as distinguished from the "common world" (). The origin of the term is attributed to fragment B89 (

Diels–Kranz numbering Diels–Kranz (DK) numbering is the standard system for referencing the works of the ancient Greek pre-Socratic philosophers, based on the collection of quotations from and reports of their work, ''Die Fragmente der Vorsokratiker'' (''The Fragmen ...

) of the

pre-Socratic philosopher Pre-Socratic philosophy, also known as early Greek philosophy, is ancient Greek philosophy before Socrates. Pre-Socratic philosophers were mostly interested in cosmology, the beginning and the substance of the universe, but the inquiries of thes ...

Heraclitus Heraclitus of Ephesus (; grc-gre, Ἡράκλειτος , "Glory of Hera"; ) was an ancient Greek pre-Socratic philosopher from the city of Ephesus, which was then part of the Persian Empire. Little is known of Heraclitus's life. He wrot ...

: "The waking have one common world, but the sleeping turn aside each into a world of his own." The term has various interpretations: is associated with

dream A dream is a succession of images, ideas, emotions, and sensations that usually occur involuntarily in the mind during certain stages of sleep. Humans spend about two hours dreaming per night, and each dream lasts around 5 to 20 minutes, althou ...

ing, imagination, and

delusion A delusion is a false fixed belief that is not amenable to change in light of conflicting evidence. As a pathology, it is distinct from a belief based on false or incomplete information, confabulation, dogma, illusion, hallucination, or som ...

; with

wakefulness Wakefulness is a daily recurring brain state and state of consciousness in which an individual is conscious and engages in coherent cognitive and behavioral responses to the external world. Being awake is the opposite of being asleep, in which m ...

reason Reason is the capacity of consciously applying logic by drawing conclusions from new or existing information, with the aim of seeking the truth. It is closely associated with such characteristically human activities as philosophy, science, ...

, and

consensus reality Consensus reality is that which is generally agreed to be reality, based on a consensus view. The appeal to consensus arises from the idea that humans do not fully understand or agree upon the nature of knowledge or ontology, often making it unce ...

. From the 1950s, the term was adopted by phenomenological/ existential psychologists, such as

Ludwig Binswanger Ludwig Binswanger (; ; 13 April 1881 – 5 February 1966) was a Swiss psychiatrist and pioneer in the field of existential psychology. His parents were Robert Johann Binswanger (1850–1910) and Bertha Hasenclever (1847–1896). Robert's Ger ...

and

Rollo May Rollo Reece May (April 21, 1909 – October 22, 1994) was an American existential psychologist and author of the influential book '' Love and Will'' (1969). He is often associated with humanistic psychology and existentialist philosophy, ...

, to refer to the experience of people with delusions or other problems who have trouble seeing beyond a limited private world of their own minds or who confuse this private world with shared reality. It was an important part of novelist Philip K. Dick's views on

schizophrenia Schizophrenia is a mental disorder characterized by continuous or relapsing episodes of psychosis. Major symptoms include hallucinations (typically hearing voices), delusions, and disorganized thinking. Other symptoms include social wit ...

, as expressed in his 1964 essay "Schizophrenia & 'The Book of Changes'", where he drew on his familiarity with the existential psychologists, Heraclitus, and the '' I Ching''.

References

Conceptual models Schizophrenia {{Philo-stub