“Yes, yes,” say the proponents of magic, “but there’s still a mystery: how can all this vivid conscious experience be physical, merely and wholly physical?” (I’m assuming, with them, that we’re wholly physical beings.) This, though, is the 400-year-old mistake. In speaking of the “magical mystery show”, Humphrey and many others make a colossal and crucial assumption: the assumption that we know something about the intrinsic nature of matter that gives us reason to think that it’s surprising that it involves consciousness. We don’t. Nor is this news. Locke knew it in 1689, as did Hume in 1739. Philosopher-chemist Joseph Priestley was extremely clear about it in the 1770s. So were Eddington, Russell and Whitehead in the 1920s.
One thing we do know about matter is that when you put some very common-or-garden elements (carbon, hydrogen, oxygen, sodium, potassium, etc) together in the way in which they’re put together in brains, you get consciousness like ours – a wholly physical phenomenon. (It’s happening to you right now.) And this means that we do, after all, know something about the intrinsic nature of matter, over and above everything we know in knowing the equations of physics. Why? Because we know the intrinsic nature of consciousness and consciousness is a form of matter.