Prediction in a complex world is a chancy business. Every decision that a survival machine takes is a gamble, and it is the business of genes to prog… - Richard Dawkins

When we look at a solid lump of iron or rock, we are 'really' looking at what is almost entirely empty space. It looks and feels solid and opaque because our sensory systems and brains find it convenient to treat it as solid and opaque. It is convenient for the brain to represent a rock as solid because we can't walk through it. 'Solid' is our way of experiencing things that we can't walk through or fall throug, because of the electromagnetic forces between atoms. 'Opaque' is the experience we have when light bounces off the surface of an object, and none of it goes through.

At the age of three and a half the Taung Child was eaten by an eagle. The evidence is that damage marks to the eye sockets of the fossil are identical to marks made by modern eagles on modern monkeys as they rip out their eyes. Poor little Taung Child, shrieking on the wind as you were borne aloft by the aquiline fury, you would have found no comfort in your destined fame, two and a half million years on, as the type specimen of Australopithecus africanus.

My untidy habits drive me to follow the slash-and-burn (or Mad Hatter) principle. Work on a virgin table until the mess becomes unbearable, then move on to a clean table in a clean room — or, on a beautiful summer day like this, one of the five tables dotted around the garden. Trash that table and move on again.