A swarm of bees, a colony of ants and a collection of neurons: three independently evolved assemblages which each constitute a thinking machine. This is convergent evolution at work again, the flowering of analogous but radically different ways of thinking and doing, all over the thicket of life.

We don’t build airplanes by reverse engineering feathers, and airplanes don’t flap their wings. Rather, airplane designs are based on the principles of aerodynamics, which all flying objects must obey. We still do not understand those analogous principles of thought.

Very recently, certain animal brains have begun to exhibit both generality of optimization power (producing an amazingly wide range of artifacts, in time scales too short for natural selection to play any significant role) and cumulative optimization power (artifacts of increasing complexity, as a result of skills passed on through language and wri