That’s the goal of the bottom up thinkers:
British science writer Philip Ball offers us a guide to a very interesting project: an attempt to “naturalize” the idea of agency, that is, make the desire to do things—the mouse’s desire to escape the cat— explainable from a fully materialist perspective.
That’s much harder than it seems. Rocks don’t desire anything. So we can’t just start from the bottom. It’s also not enough to say that the mouse wants to avoid getting killed. That’s true but it doesn’t really explain anything.
For example, a person looks both ways before crossing the street to avoid getting run over. But, by itself, that doesn’t explain why she tries to avoid getting run over. One must factor in her memory, background knowledge, will to live, and such, to explain her behavior. A tire rolling downhill would not alter its course even though it might get run over because it does not have any mental attributes.
There is no science explanation, at present, for why life forms, human, animal, plant, or bacterium, strive to go on living but rocks do nothing to avoid becoming sand.Denyse O’Leary, “Can we find purpose in a universe with no underlying purpose?” at Mind Matters News
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