Awhile back, maybe 9 months, I argued for the causal closure of nature. SInce then, I have been reading up on analytic debates in metaphysics, particularly emergence. It has become apparent that what I meant by “causal closure” is not what what they mean, and perhaps I was and have been misunderstood.
In naturalism, especially physicalism or materialism, causal closure usually includes both an affirmation of what is real (the physical-energetic) under some level of analysis and a denial of the supernatural (e.g., events that violate efficient causality or the laws of nature). In short, it is a thesis about what is real and how it behaves.
When I claimed causal closure, I was not affirming what was real. In fact, I reject any hard-nosed exclusion as trying to make an unverifiable universal proposition about the cosmos. I have sympathy with William James on this point; we should make our assumptions but not be blinded by them. Who knows, maybe God is natural? But this is beside the present point.
In mathematical terms, which was guiding my discussion, I wrote that the operations of nature are closed, which is not the same as saying the the domain of nature is closed. That is, any activity in nature begets something natural, but that doesn’t mean that the product is of the same stuff as before. I embrace real creativity. This is a wide divergence from the naturalisms common to analytic philosophy, which are also commonly committed to what is real. I just require it to be part of a system of nature, where “nature” is a open concept. Creativity of this sort implies emergence and non-reducibility.
What does this openness mean in principle? I am open not only to “structural” or “systemic” causation, but also new material causation. This is possible on the view that the laws of nature are hyper-stable, but neither logically nor physically necessary. This is also related to evolutionary metaphysics.
In terms of my recent posts on emergentism, I might not be accepted into the camp of “naturalism” by contemporary standards. But if that is the case, then none of the classical pragmatists or many contemporary Americanists would be.
For clarification, John Symons tells me that “physicalism” presumes reducibility to micro-physics, whereas “materialism” does not, and I would like to thank him for the clarfication.