Twentieth-century, mostly, so all of this is paraphrase. Go read them.

Terence McKenna, Food of the Gods (1992)

Speculative and deliberately provocative. He argued that plants altered human consciousness early in our history and shaped culture and language. Many researchers reject the central claim; it is here as a provocation, not as settled science.
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Marshall McLuhan, Understanding Media (1964)

The medium is the message (that's the first chapter's title). The form of a technology changes us more than its content.
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Julian Jaynes, The Origin of Consciousness in the Breakdown of the Bicameral Mind (1976)

Consciousness as a learned, recent, cultural thing; ancient minds hearing their own thoughts as gods. See other minds.
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Daniel Dennett, Consciousness Explained (1991)

No Cartesian theater; multiple drafts. Arguably it explains consciousness away, which he'd say is the same thing.
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Thomas Nagel, "What Is It Like to Be a Bat?" (1974)

Subjective experience might not be capturable by any objective description.
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Alan Turing, "Computing Machinery and Intelligence" (1950)

The imitation game. See Turing.
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Aldous Huxley, The Doors of Perception (1954)

The title is from Blake. That's how he got onto this shelf.
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