Mind at Large
Mind at Large is a concept proposed by Aldous Huxley to help interpret psychedelic experience. He maintained that the human mind filters reality under normal circumstances and that psychedelic drugs remove the filter, exposing the user to a Mind at Large.
Huxley held that psychedelic drugs could disable filters which inhibit or quell signals related to mundane functions from reaching the conscious mind. In the aforementioned books, Huxley explores the idea that the human mind filters reality, partly because handling the details of all of the impressions and images coming in would be unbearable, partly because it has been taught to do so. He believes that psychoactive drugs can partly remove this filter, which leaves the drug user exposed to Mind at Large.
During an experiment conducted by the British psychiatrist Humphrey Osmond in 1953, Huxley was administered the psychedelic drug mescaline, and was prompted by Osmond to comment on the various stimuli around him, such as books and flowers. Huxley recorded aspects of their conversation in The Doors of Perception, focusing on what he said in the recordings. He observed that everyday objects lose their functionality, and suddenly exist "as such"; space and dimension become irrelevant, with perceptions seemingly being enlarged, and at times even overwhelming.
Huxley wrote in The Doors of Perception:
Each person is at each moment capable of remembering all that has ever happened to him and of perceiving everything that is happening everywhere in the universe. The function of the brain and nervous system is to protect us from being overwhelmed and confused by this mass of largely useless and irrelevant knowledge, by shutting out most of what we should otherwise perceive or remember at any moment, and leaving only that very small and special selection which is likely to be practically useful. According to such a theory, each one of us is potentially Mind at Large.
In the same book, Huxley stated:
In the final stage of egolessness there is an 'obscure knowledge' that All is in all—that All is actually each. This is as near, I take it, as a finite mind can ever come to 'perceiving everything that is happening everywhere in the universe.'