Stream of consciousness refers to the flow of thoughts in the conscious mind. Research studies have shown that we only experience one mental event at a time as a fast-moving mind stream.William James, often considered to be the father of American psychology, first coined the phrase "stream of consciousness". The full range of thoughts--that one can be aware of--can form the content of this stream.
Early Buddhist scriptures describe the "stream of consciousness" (Pali; viññ?na-sota) where it is referred to as the Mind Stream. The practice of mindfulness, which is about being aware moment-to-moment of one's subjective conscious experience aid one to directly experience the "stream of consciousness" and to gradually cultivate self-knowledge and wisdom. Buddhist teachings describe the continuous flow of the "stream of mental and material events" that include sensory experiences (i.e., seeing, hearing, smelling, tasting, touch sensations, or a thought relating to the past, present or the future) as well as various mental events that get generated, namely, feelings, perceptions and intentions/behaviour. These mental events are also described as being influenced by other factors such as attachments and past conditioning. Further, the moment-by-moment manifestation of the "stream of consciousness" is described as being affected by physical laws, biological laws, psychological laws, volitional laws, and universal laws.
In his lectures circa 1838-1839 Sir William Hamilton, 9th Baronet described "thought" as "a series of acts indissolubly connected"; this comes about because of what he asserted was a fourth "law of thought" known as the "law of reason and consequent":
In this context the words "necessarily infer" are synonymous with "imply". In further discussion Hamilton identified "the law" with modus ponens; thus the act of "necessarily infer" detaches the consequent for purposes of becoming the (next) antecedent in a "chain" of connected inferences.
He was enormously skeptical about using introspection as a technique to understand the stream of consciousness. "The attempt at introspective analysis in these cases is in fact like seizing a spinning top to catch its motion, or trying to turn up the gas quickly enough to see how the darkness looks." However, the epistemological separation of two levels of analyses appears to be important in order to systematically understand the "stream of consciousness."
Conceptually understanding what is meant by the "present moment," "the past" and "the future" can aid one to systematically understand the "stream of consciousness."
Susan Blackmore challenged the concept of stream of consciousness. "When I say that consciousness is an illusion I do not mean that consciousness does not exist. I mean that consciousness is not what it appears to be. If it seems to be a continuous stream of rich and detailed experiences, happening one after the other to a conscious person, this is the illusion." However she also says that a good way to observe the "stream of consciousness" may be to calm the mind in meditation. Suggestions have also been made regarding the importance of separating "two levels of analyses" when attempting to understand the "stream of consciousness."
In literature, stream of consciousness writing is a literary device which seeks to portray an individual's point of view by giving the written equivalent of the character's thought processes, either in a loose interior monologue, or in connection to his or her sensory reactions to external occurrences. Stream-of-consciousness as a narrative device is strongly associated with the modernist movement. The term was first applied in a literary context, transferred from psychology, in The Egoist, April 1918, by May Sinclair, in relation to the early volumes of Dorothy Richardson's novel sequence Pilgrimage. Amongst other modernist novelists who used it are James Joyce in Ulysses (1922) and William Faulkner in The Sound and the Fury (1929).