Neither ecological nor social engineering will lead us to a conflict-free, simple path . . . Utilitarians and others who simply advise us to be happy… - Mary Midgley

In fact, the whole idea of illusion seems to make sense only if we accept the reality of the illusory experience as an experience and question only what it seems to be telling us about the outside world. Optical illusions do really hapen. What they can’t do is provide accurate measurements of the outside world. The idea of having, so to speak, two successive layers of illusion here is unworkable.

But understanding and explaining motives does not compromise freedom; nor does even predicting acts necessarily do so. A person committed to a political cause may vote predictably, and intelligibly in an election. He does not vote less freely than someone that flips a coin at the last minute. So if we find comparison with animals any help in understanding motives, it will not mean that conduct is not free. And since animals are not (as Descartes supposed) automata, the issue of freedom does not make comparing man with any other species and downgrading irrelevance.

All moral doctrine, all practical suggestions about how we ought to live, depend on some belief about what human nature is like.