INTUITION PUMPS AND OTHER TOOLS FOR THINKING

A famous thinker demonstrates how he does his job.

Thinking is hard, writes Dennett (Philosophy/Tufts Univ.; Breaking the Spell: Religion as a Natural Phenomenon, 2006, etc.), who then proceeds to explain how to do it right. He stresses that history’s philosophical giants have relied on vivid, although not necessarily accurate, thought experiments, which he dubs "intuition pumps” (Plato’s Cave, Descartes’ evil demon, Kant’s categorical imperative). Dennett begins with a dozen general-purpose tools, from the popular reductio ad absurdum (examine a statement for preposterous implications) to a warning to watch out for the deepity, a proposition that seems profound only because it’s ambiguous (“Love is just a word”). Having delivered these devices, he goes on to show how they illuminate or, equally often, shoot down arguments on great philosophical subjects such as consciousness, evolution and free will, as well as revealing the thought processes of philosophers themselves, with emphasis on those with whom Dennett disagrees. A well-known materialist, he has no patience with explanations that involve “magic,” whether it is a god who creates everything, an evolutionary structure too complex to result from a natural process or a human mind with secrets beyond the reach of science. Those who deny that one can compare the brain to a gigantic computer don’t understand how computers work. Much of their operation appears genuinely magical but isn’t.

Despite a generous helping of wit and amusing anecdotes, this is not Philosophy for Dummies. Many of the short chapters require close attention and rereading, but those willing to work will come away with a satisfying understanding of how deep thinkers think.