In government, bicameralism (Latin bi, two + camera, chamber) is the practice of having two legislative or parliamentary chambers compromise bills.

Bicameralism is an essential and defining feature of the classical notion of mixed government. Bicameral legislatures tend to require a concurrent majority to pass legislation.

Although the ideas on which bicameralism are based can be traced back to the theories developed in Ancient Sumer and later ancient Greece, ancient India, and Rome, recognizable bicameral institutions first arose in medieval Europe where they were associated with separate representation of different estates of the realm. For example, one house would represent the aristocracy, and the other would represent the commoners.

The Founding Fathers of the United States also favored a bicameral legislature. The idea was to have the Senate be wealthier, and (apparently) wiser. "The Senate was created to be a stabilizing force, elected not by mass electors, but selected by the State legislators. Senators would be more knowledgeable and more deliberate—a sort of republican nobility—and a counter to what Madison saw as the 'fickleness and passion' that could absorb the House.

Julian Jaynes (February 27, 1920 – November 21, 1997) was an American psychologist, best known for his book The Origin of Consciousness in the Breakdown of the Bicameral Mind (1976), in which he argued that ancient peoples were not conscious.

Jaynes defines "consciousness" more narrowly than most philosophers. Jaynes' definition of consciousness is synonymous with what philosophers call "meta-consciousness" or "meta-awareness" i.e. awareness of awareness, thoughts about thinking, desires about desires, beliefs about beliefs. This form of reflection is also distinct from the kinds of "deliberations" seen in other higher animals such as crows insofar as Jaynesian consciousness is dependent on linguistic cognition.

Jaynes wrote that ancient humans before roughly 1200 BC were not reflectively meta-conscious and operated by means of automatic, nonconscious habit-schemas. Instead of having meta-consciousness, these humans were constituted by what Jaynes calls the "bicameral mind". For bicameral humans, when habit did not suffice to handle novel stimuli and stress rose at the moment of decision, neural activity in the "dominant" (left) hemisphere was modulated by auditory verbal hallucinations originating in the so-called "silent" (right) hemisphere (particularly the right temporal cortex), which were heard as the voice of a chieftain or god and immediately obeyed.

Terence Kemp McKenna (November 16, 1946 – April 3, 2000) was an American philosopher, psychonaut, researcher, teacher, lecturer and writer on many subjects, such as human consciousness, language, psychedelic drugs, the evolution of civilizations, the origin and end of the universe, alchemy, and extraterrestrial beings.

Terence McKenna grew up in Paonia, Colorado. He was introduced to geology through his uncle and developed a hobby of solitary fossil hunting in the arroyos near his home. From this he developed a deep artistic and scientific appreciation of nature.

At age 16, McKenna moved to Los Altos, California to live with family friends for a year. He finished high school in Lancaster, CA. In 1963, McKenna was introduced to the literary world of psychedelics through The Doors of Perception and Heaven and Hell by Aldous Huxley and certain issues of The Village Voice that talked about psychedelics.

McKenna claimed that one of his early psychedelic experiences with morning glory seeds showed him "that there was something there worth pursuing." In an audio interview Terence Mckenna claims to have started smoking cannabis regularly during the summer following his 17th birthday.