Words are our servants, not our masters. - Richard Dawkins

Things exist either because they have recently come into existence or because they have qualities that made them unlikely to be destroyed in the past.

It really comes down to parsimony, economy of explanation. It is possible that your car engine is driven by psychokinetic energy, but if it looks like a petrol engine, smells like a petrol engine and performs exactly as well as a petrol engine, the sensible working hypothesis is that it is a petrol engine.

We admit that we are like , but we seldom realise that we are apes. Our common ancestor with the chimpanzees, bonobos and gorillas is much more recent than their common ancestor with the Asian apes — the and orangutans. There is no natural category that includes chimpanzees, gorillas and orangutans but excludes humans.