Understanding Intelligence by Rolf Pfeifer and Christian Scheier, MIT Press, price £37.50, ISBN 0262161818

IF YOU want to understand how a machine works, take it apart and put it back together. That's not, of course, an option for understanding the brain-you'd find yourself with nothing but a sticky mess.

So why not do the next best thing: build your own simple creature, a robot, and see how that works. Surely with the power of today's computers we can put together something that has limited intelligence, and studying that might give us insight into the workings of a living brain.

Unfortunately, when it comes to building mobile robots that can look after themselves, the classical artificial intelligence notion that "brain equals computer" is a non-starter. Sojourner, the rover that flew on the Mars Pathfinder mission, was hailed as a success, yet it did not have the native intelligence of a woodlouse. ...