A: So, if the eye were an animal, vision would be its soul.
B: That’s what he says.
A: And you take that to mean that vision is both cause and effect of the eye in different ways: that we have a harmony (now called a “mechanist”) account of soul as an effect of complex parts, while the soul is also a source of genesis and continued existence.
B: Right. Vision explains facts about embryogenesis, why the body attacks certain things causing eye disease, and why it takes in certain nutrients that allow it to rebuild cells in the lens, to nourish the muscles that adjust focus, to swat out and flush out particles that fly into the eye, etc.
A: All this doesn’t object to the historical fact that eyes were selected for by chance, and might not have arisen from any plan in nature.
B: I’d prefer to say that but chance plays a role in the plan, like a coin-flip that the beginning of the game or the number-jostler in a bingo game, but sure, all this is in keeping with eyes arising from chance.
A: Fine, but your basic idea makes no sense. Speaking about vision prior to the eye is like talking about waterless waves or knowledge without a knower. In fact, I think this is exactly what you’re arguing for! If the mind were an animal, knowledge would be its soul!
B: But this is just how we find nature. Embryogenesis, immune responses, building tissues, etc. are all execution of plans. If “Plan” is too much of a metaphor, we might say that the present part of all these actions (talking in the right nutrient at time T) is clearly a part of a larger whole (nourishing the muscle at T + x). What is happening makes no sense except in relation to a whole that is both given and coming to be. In fact, this is just what a “process” is, and nature clearly follows processes.
A: You’ve got to pick: either the whole exists or it is coming to be.
B: Why’s that? Isn’t this just a variant of the Parmenides/Aristotle problem?
A: Maybe that’s right – we could take Aristotle’s final cause as being a way of saving the truth of Parmenides (and later Einstein). Every process must be somehow whole and given – for Aristotle it is given through the he ho heneka or “for the sake of which”.
B: The final cause.
A: Right, if by “final” we mean “the whole”, or complete actuality.
B: If that’s how we take it, then natural things are never whole all at once.
A: Right. They’re historical too, and to exist like that is to never be all at once.
B: So now you want history to be a whole in one sense and not in another? Or is that what I was saying?
A: You’re the one who wants wholes to both be there and not be there.
B: Yes. What else is a process? It’s paradoxical, but that’s just how we find nature.
A: So are you saying that, so far as nature is a unified process, it is already given even while it is being worked out?
B: Yes. That’s true of any process. Try to picture “pregnancy” in a way that could forever do without a timeline stretching from conception to implantation to birth. Still, at any given time one has either conception or implantation or development or birth. Saying that pregnancy is a whole process is a large part of what one means by its having a “final cause”.
A: But aren’t we proving too much now? Now everything is a whole, including all of nature! Why is it not alive?
B: I’m happier proving too much. This is another reason why we lose sight of soul. Let a thousand souls of things bloom.
A: This is pantheism.
B: Or maybe “soul” is only a whole that somehow depends for its being on the process.
A: There you go- wanting a soul to depend on the thing that arises and to pre-exist to it.