According to Dennett, Director of the Center for Cognitive Studies at Tufts University, human consciousness is neither the “ghost in the machine” of the dualist nor the “audience in the theater” implicit in many materialist models. Consciousness just is the working of the various physical subsystems of the brain, but it is “smeared out” over those subsystems; there is no center of human conscious experience. His “Multiple Drafts” theory likens consciousness to the working of a word processing program. The brain’s discriminator systems (which, for example, detect movement or identify a familiar face) all produce versions or “drafts’ of the present moment, and each clamors for attention, though it seems as if a single consciousness is present. This effect is partly the result of the evolutionary hard-wiring of brain systems, but it is mostly the result of the “mind-forming” activities of ideas (such as self-identity, pizza, or clothing) that come to reside in human brains.
These ideas organize or “cobble together” reports from the brain’s subsystems so that it appears there is only a single continuous train of consciousness. Yet Dennett points out that human consciousness is full of gaps and can come apart (as Multiple Personality Disorder indicates); further, what seem to be images in the “mind’s eye” are nothing more than the various computations produced by the brain. The brain does not turn on a blue light in any Theater of Consciousness when one thinks of the sky; rather, the subjective sensation of blue is nothing but the computations of memory circuits.
CONSCIOUSNESS EXPLAINED may not make many converts, yet Dennett’s exploration is provocative, rich in ideas, and in its own way, consciousness raising.
Sources for Further Study
Booklist. LXXXVIII, October 1, 1991, p. 222.
Boston Globe. November 3, 1991, p. 94.
Kirkus Reviews. LIX, September 15, 1991, p. 1194.
London Review of Books. XIII, November 21, 1991, p. 3.
Los Angeles Times Book Review. November 24, 1991, p. 6.
The New Republic. CCV, December 23, 1991, p. 40.
The New York Times Book Review. XCVI, November 10, 1991, p. 1.
Publishers Weekly. CCXXXVIII, August 16, 1991, p. 41.
Science News. CXL, December 14, 1991, p. 395.
The Wall Street Journal. November 7, 1991, p. A12.