I believe that there is no fundamental meaning to a discrete self or mind, because the reductionist standpoint, that a person can be described entirely in terms of their physical constituents, does not demand a division between, for instance, the electrical impulses in the brain, the photons that provoke them, the body off of which they reflect, and the electrical impulses in the brain of that body; there is no fundamental cutoff point between self and other. One could, perhaps, take the view that the brain is thereby interwoven with everything else and thus governs it, but this abstraction conflicts with the original reductionist premise. Instead, I conclude that since there is nothing to set the mind apart as unique, it has no role in the shaping of reality. Of course, this is in no way a proof that perception does not control reality, as it assumes that the laws of physics do so; instead, it is simply a demonstration that the philosophy is self consistent, and the existence of the mind does not conflict with the existence of an independent truth.
Assuming that the mind is the arbitrarily defined sum of its physical components, reacting to the universe and affecting it only by direct physical action, there is no reason to presume that its perception of that universe is accurate; in fact, it would be rather surprising if the mind was somehow perfectly attuned to reality. However, it operates on the large scale in roughly the same manner as it does on a small scale- cause and effect, input and output, build logic just as they build nature. If A and B and C, then D; if hydrogen and oxygen and heat, then water (Of course, the cause and effect is much more complicated here, and I am ignoring quantum uncertainty, because I see no reason to believe that it has any real relevance to my argument, which depends ultimately on reductionism; determinism is only relevant for the creation of logic insofar as the brain observes it; that is, on a macroscopic level). So the brain, through observation, has learned a system of thought which mirrors the world as it sees it, and the extension of this logic beyond observation has proved reliable to a point that, as I argued above, goes beyond the simple matching of perception to the brain’s conclusions. So the brain, while a fundamentally flawed and subjective observer, seems to have created an axiomatic system that is a good if not a perfect reflection of an existing reality, without creating any of that reality itself. Again, I am assuming the existence of a reductionist truth, and am simply demonstrating consistency, but see little reason to assume another philosophy. I’m not sure I properly understood what it is you are getting at, however.