Some complained that I didn’t include a question on consciousness in my list of big questions. My reason is that I can’t see how we will ever know more than we do now. There’s nothing to learn:

Zombies are supposedly just like real people in having the same physical brains, which arose the through the same causal history. The only difference is that while real people really “feel”, zombies do not. But since this state of “feeling” is presumed to have zero causal influence on behavior, zombies act exactly like real people, including being passionate and articulate about claiming they are not zombies. People who think they can conceive of such zombies see a “hard question” regarding which physical systems that claim to feel and otherwise act as if they feel actually do feel. (And which other systems feel as well.)

The one point I want to make is: if zombies are conceivable, then none of us will ever have any more relevant info than we do now about which systems actually feel. Which is pretty much zero info! You will never have any info about whether you ever really felt in the past, or will ever feel in the future. No one part of your brain ever gets any info from any other part of your brain about whether it really feels.

These claims all follow from our very standard and well-established info theory. We get info about things by interacting with them, so that our states become correlated with the states of those things. But by assumption this hypothesized extra “feeling” state never interacts with anything. The actual reason why you feel compelled to assert very confidently that you really do feel has no causal connection with whether you actually do really feel. (More)

Your brain is made out of quite ordinary physical materials, driven by ordinary physical processes that we understand very well at near-atomic levels of organization. It is only processes at higher levels of organization that we haven’t traced out in detail. We will eventually be able to trace in great detail and at all levels the causes of what makes you, or an em, or any variation on either, inclined to passionately claim, and believe, that you really do feel. And that will let us predict well what changes to you, or anything, might induce you, or it, to claim or believe something different.

But if you insist that none of that can possibly verify that you, or an em, actually do feel, then it can’t add any info on that issue. Yes, maybe you have intuitions inside you that often tell you if you think something that you see in front of you really feels. But such intuitions are already available to you now. Just imagine various things you might see, note your intuitions about each, compare those to others’ intuitions, and then draw your conclusions about consciousness. After all, we already have a pretty good idea of all the things we will eventually be able to see.

Okay, yes, you are probably in denial about how much the intuitions of others would influence yours, and about how strong would be the social pressures on your intuitions to accept that ems feel, if in fact you lived in a would where ems dominated. I predict that in such a situation most would accept that ems feel. Not because new info has been offered, but because of familiar social pressures. And yes, we can learn more about how our intuitions respond to such pressures. But that won’t give us any more info on the truth of what “really” feels.