You don't know what physical things are any more than you know what thought is; they have their different ways of being but what they are is not explained by talk of mind or matter. That distinction has pragmatic force but no value at all as metaphysics. There is no reason to conclude that they are different sorts of being. And the same goes for you who are engaged with them. You have your particular way of absence from all appearance; that's a way of being distinctive but no different essentially from that of those other kinds of things. Being you might say is no more characterised by the modes of objective things than by subjective or absent things. Duality is fine but posterior to being. Being doesn't melt away under radical pragmatism, rather, what did melt away was never being in the first place.