But what if there is no substance - or anything we can identify as such? What if everything is energy, and substance and form are just flawed modes of human perception?
I agree with you that metaphysics is quite a mess. But, IMHO, you are limiting yourself in both the questions you can pose, as well as the answers you can provide, if you require all metaphysical ideas to mesh with those of physics. Part of the goal of metaphysics is to pose questions and give answers that physics may not be able to. Again, just my opinion. Obviously I'm not completely a materialist. I'd be interested in reading your paper, btw.
There isn't. That's my point. Nothing that can be known meets the criteria for being called "substance." If it can't be known, then it's of no use. So, a useful metaphysics would be one that deals with things that can be known. But a metaphysics that deals with things that can be known isn't really a metaphysics at all, it's just physics. So, we have to turn metaphysics into physics. That's what I've said so far. Yes, I certainly am. But that seems desirable to me. I'm not either. I think an electron is a good example of something that is probably not material. The mind, in the way cognitive scientists look at it anyway, is also probably immaterial, I think. The real difference between us is that I don't think metaphysical questions can be answered, even if the questions posed are meaningful. You seem to believe that they can be answered for some reason. Maybe I'll post it when it's done. I'll have to wait a little while after that even in case they decide to check it for plagarism. But yeah, I can post it. It won't be great. I've written better.
Re: my reference to Gurdjeif: I remember from reading his teachings that he once said, at length, that there is no such thing as immaterial spirit, or a state that transcends matter. He said that all is matter, and that the states and beings (including Higher Beings, Angels, etc, BlackBillBlake) we consider "spiritual" are simply finer, more subtle states of matter that our broken bodymindsoul machinery cannot relate to with accurate perception nor appropriate communication...cuz again, we are broken machines. I see the spiritual language also as coded; a man that much ahead of his time needs to "speak in parables", because the framework of his ideas has not been sufficiently developed scientifically. There was no Computational Theory of Mind in 1920, but look at old G go with the hints....broken machines, indeed! G's use of terms like "many changing 'I's" calls to mind the Minsky book Society of Mind. Wikipedia: In a step-by-step process, Minsky constructs a thesis for a way in which human intelligence in all its complexity can be built up, layer by layer, from the interactions of simple parts called agents, who are themselves mindless. He describes the postulated interactions as constituting a "Society of Mind", hence the title. Re: my Jainist inclusion: I will simply and easily defer to a more knowledgable opinion such as Bhaskar's , cuz I do not know much at all about Jainism, but I was under the impression that their practical everyday stance is to entirely ignore metaphysics as basically meaningless to a life well lived in a physical world of cause and effect. That to me, no matter the traditional-philosophical underpinnings, describes a basically material focus.
Personally, I am first a naturalist. From that comes my materialism (which is naturally correct, as it seems to me), and anarchist philosophy, and from those come my atheism.