Abstract: We have no grounds for supposing that a foetus has a soul until it is conscious, and no grounds for supposing that it is conscious until there occur in it brain processes similar to those that accompany consciousness in more developed human brains. The higher animals have souls. While scientists may discover vast numbers of correlations between mental events and brain events, it is most improbable that they will be able to explain why there are the correlations that they are, or any correlations at all – that is, why neural systems of a certain complexity give rise to souls. The very success of science in achieving vast integrations of theories in physics and chemistry was achieved by separating off from the physical world colours, tastes etc; but this cannot be done when we are looking for a theory with psychophysical laws.

Keywords: animals, Aquinas, brain processes, complexity, consciousness, Darwin, Davidson, foetus, psychophysical laws, soul,