> It does however seem to stop when the brain is destroyed, which makes it unlikely to be present in fundamental particles, or in parts of a disintegrated brain

Does consciousness really "seem to stop" when the brain is destroyed? We can't directly observe anyone's consciousness other than our own. It is true that, when people die, we cease to have access to the outward signs we use to infer they are conscious – but we don't know whether that's because their consciousness has ceased, or whether that is because it has "gone somewhere else" to which we don't currently have access. We never have direct access to the inner reality of consciousness for anyone other than ourselves, and we can only know the temporary cessation of our own consciousness, its permanent cessation (if that is possible) is in principle unknowable to us.

Speaking of our consciousness "going somewhere else" at death (an afterlife) doesn't have to be a religious claim – there are heaps of "naturalistic" ways in which consciousness might survive death (e.g. Boltzmann brains, computer simulations, quantum immortality). Since we don't know whether any of those ways actually happen, we don't know whether or not consciousness actually stops at death.

But I also have other organs, such as my stomach, and arbitrary lumps of matter such as my elbow and my bicycle, none of which are sufficient to maintain the outward signs of consciousness after the brain is destroyed (or merely dosed with gin). So consciousness, which apparently resided in the brain and then went away when the brain was disrupted, didn't go to any of those places. Similarly, when my stomach ceases to digest or my bicycle ceases to roll forward, the digestive function doesn't migrate to the brain and the rolling function isn't taken over by the elbow. So we can choose in each case between the hypothesis "physically stopped working" or "metaphysically sent its function to another mysterious place", and again I'll appeal to parsimony on this one: why should the function be transferred somewhere mysterious by a means outside of our experience and ability to explain? And why make this claim about consciousness alone, out of all the functions that things in the world have? There's a kind of fallacy going on here along the lines of "I can't fully explain what this thing is, therefore every kind of mysterious and magical supposition can be roped into its service and claim plausibility."

> And why make this claim about consciousness alone, out of all the functions that things in the world have?

Because consciousness is fundamental in a way none of those things in the world are. It is only through our own consciousness that we can know those other things exist, indeed that we can ever know anything at all. Treating consciousness as just a thing among things ignores that it is essential, foundational, to all other things as we know them, as we can know them.