Consideration of motives brings up the matter of free will. I had better say once, that my project of taking animal comparisons seriously does not in… - Mary Midgley

The motivation of living creatures does got boil down to any single basic force, not even an 'instinct of self-preservation.' It is a complex pattern of separate elements, balanced roughly in the constitution of the species, but always liable to need adjusting. Creatures really have divergent and conflicting desires. Their distinct motives are not (usually) wishes for survival or for means to survival, but for various particular things to be done and obtained while surviving. And these can always conflict. Motivation is fundamentally plural. . . An obsessive creature dominated constantly by one kind of motive, would not survive.

Let us start by considering why the attempt to glorify science on its own cannot work. This is because human thought operates as a whole. It is an ecosphere, a vast and complex landscape, including, but not confined to, common sense. Science itself is, of course, not a single compartment but a large, thickly wooded area comprising many sciences, an area that merges into those around it. Those sciences vary from physics to anthropology and all of them are shot through with problems coming from areas outside them, such as philosophy and history. Biology, for instance, has to deal with philosophical problems about the concept of life and also with vast historical problems about evolution for which it uses historical methods, not those of physics.

Selection does not work by cutthroat competition between individuals, but by favouring whatever behavior is useful to the group. People with crude notions of "Darwinism" make an intriguing blunder here. They refuse the mere fact of competing, that is, of needing to share out a resource with the motive of competitiveness or readiness to quarrel.