The issue is not between bad guys who use and "adversary" approach and good guys who are scientific and impartial...Everybody, including himself is p… - 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.

The notion that we "have a nature" far from threatening the concept of freedom, is absolutely essential to it. If we were genuinely plastic and indeterminate at birth, there could be no reason why society should not stamp us into any shape that might suit it. The reason people view suggestions about inborn tendencies with such indiscriminate horror seems to be that they think exclusively in one particular way in which the idea of such tendencies has been misused, namely, that where conservative theorists invoke them uncritically to resist reform. But liberal theorists who combat such resistance need them just as much, and indeed, usually more. The early architects of our current notion of freedom made human nature their cornerstone. Rousseau's trumpet call "Man is born free, but everywhere he is in chains," makes sense only as description of our innate constitution as something positive, already determined, and conflicting with what society does to us. Kant and Mill took similar positions. And Marx, though he officially dropped the notion of human nature and attacked the term, relied on the idea as much as anybody else for his crucial notion of Dehumanization.

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.