Biologism -- the belief that human beings are essentially animals and can be understood in biological terms -- is gaining increasing acceptance in contemporary thought. This trend is seemingly legitimised by genuine, often spectacular, advances in biological science: in human genetics, evolutionary theory and neuroscience. Our propensities, we are told, can be accounted for by "a gene for" this or that; everyday behaviour can be explained in Darwinian terms; and human consciousness is identified with the activity of the evolved brain. Ultimately, so the story goes, all that we do, think and feel is subordinated to the imperative of ensuring that we behave in such a way as to, individually or collectively, maximise the chances of replicating our genetic material.
