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Dennett looks at simple choice mechanisms in early forms of life and discusses how these could have evolved into complex decision procedures and so into what we know as freewill. This leads on to questions of morality. Dennett takes a detailed look at altruism and at what actions can be thought of as 'genuinely' altruistic.
Dennett seems very much taken with Conway's Game of Life. I wasn't totally convinced about the usefulness of this. On the one hand it does allow you to think of how life might be simulated on a computer. On the other it seems that all he shows is that a computer can model a much slower computer.