Q: What does the evolutionary origin of the mind entail for metaphysics? Does this mean it is hopeless? (Let us leave aside the challenge of how we could know the truth of evolution without metaphysics.) Assuming evolutionary origins of our cognitive structures, does this leave us a basis for metaphyics and fundamental ontology?
A: I say yes; evolution does not make metaphysical science impossible. In my view, we have to accept the evolutionary origin of the science of being qua being before we can have any hope of doing it properly. Without the evolutionary context, we cannot know what we are doing. Imagine trying to reverse engineer a complex device without knowing its function; that what metaphysics has been doing for most of its history. At least, that is what the following seeks to establish.
For the sake of argument, let us assume that:
- From an evolutionary perspective, “all that matters” is adaptive fitness.
- Thus a naturally evolved creature will not necessarily evolve to know the truth, but merely encode useful rules for behavior.
The best example for number 2 above (creatures who do not care for nor need the truth). are plants. Plants have no “behavior” at all in the sense that we animals normally use that term. They have no cognitive functions as we animals normally use that term. Thus they have no cognitive structures with any relationship to truth at all. However, they are very successful. So obviously realism is optional for evolution.
There are numerous downsides to human-level cognition, for example 20% of our calories go to our brain, and it makes our childhood rather long.
So just as there is no necessary reason of evolution to favor the truth, there is also no necessary reason for evolution to favor any sort of mental faculties at all.
But the lack of necessary reasons for x does not entail lack of contingent reasons for x. For example, evolution does not necessarily favor flight or walking or photosynthesis or slithering or any number of survival strategies; all of these are contingent features of life. However, each of them has a place because increasing fitness entails a diversity of adaptive strategies. Mammals are more successful than birds or dinosaurs because our underlying “bauplan” is much more flexible w.r.t. a wide variety of adaptations: digging, swimming, flying, etc. And the use of intelligence also makes humans more flexible to adapt to or even create a wide variety of ecological niches, including space. But even if we restrict ourselves to pre-modern technology, humans are the most widely adapted mammal in the world. No other primate even comes close, although primates are not all that successful compared to rodents. But still, we are the only large animal who has a chance of surviving the destruction of our planet in 5 billion years. Not bad.
Of course, this only speaks to the evolution of “mind”, and not of the realism from the OP. But if mind is contingent, then realism is doubly so, for the same reason.
In my view, scientific realism is only a refinement of everyday naive realism. The fact that we believe in the realism of common everyday objects is not necessary either; we could evolve to treat our daily phenomenology as a mere game. But this latter attitude would also be just as contingent a possibility as the realist attitude.
In my view the temptation to be non realist about life in general is a symptom of reading only modern thinkers to the exclusion of Aristotle. Surely Aristotle was mistaken on a great many counts, but his basic methodology is still useful to avoid the many pitfalls of both analytic and Continental thought.
I say all of this in the context of believing that the content of first philosophy is simply the reverse-engineering our our human operating system as distinct from the surface grammar of our language. But just because there is an empirical / a posteriori aspect to metaphysics does not mean it is not possible as a science of being qua being.
Assuming that our mind does process information successfully, there is no reason to suspect that it cannot be reverse-engineered. By “successfully”, I mean that is reaches a decision based on input that achieves the relevant function and outcompetes other ways of avoid extinction.