"You might even believe you were happy and self-deceived; but you would not in fact be happy and self-deceived."

As far as I've got this happiness thing figured out, you're it when you believe you are, and you're not when you believe you're not. There is, in fact, not necessarily a correlation between how happy a person should be, and how happy they feel. Feelings don't have to correspond to reality. One can consciously choose to no longer be bothered by something and just be happy instead. For me at least, with a little effort, it works. And it can be validated just as easily, just by stating that my sole utility function is to be happy. The human brain is a lotus-eater machine.

If you spend a year or two working on the domain, then, if you don't get stuck in any blind alleys, and if you have the native ability level required to make progress, you will understand it better. The apparent difficulty of problems may go way down. It won't be as scary as it was to your novice-self.

Actually, one notices this effect after 3 courses in college. If you practice, related problems become easier to solve. And I guess that's as close to a universal rule as I'll get any time soon.

The hope is that it takes less courage to visualize an uncomfortable state of affairs as a thought experiment, than to consider how likely it is to be true. But then after you do the former, it becomes easier to do the latter.

And again you manage to condense a wise life lesson to two sentences. I should really write them down.

You really should write a book. Seriously. I could probably raise the hypothesis of teaching Rationality as a first-year course (as a follow-up to Logic) instead of useless "password" classes like I've received at my college. Having a book I could wave around with to convince people maybe being rational is important when you're a scientist would help a lot. At least I'd start printing and distributing it.

You could also just put the primary sequences of this website into a (e)book format, and release it. You might reach a wider audience that way, which would of course be Winning.

plus the fact of the host choosing to open door #2.

As long as I don't know his motives (or on what level the host is playing, to put it in HPMOR terms) I can't infer anything from what the host does. He might have opened door 2 because the money isn't behind door 1 and I get another chance. Or because it is behind 1 and he wants me to switch so the company can keep the money. Knowing I should integrate his motives into the equation doesn't mean I can.

Or am I missing something essential here?

Not every change is an improvement, but every improvement is necessarily a change. You cannot obtain more truth for a fixed proposition by arguing it; you can make more people believe it, but you cannot make it more true. To improve our beliefs, we must necessarily change our beliefs.

I know this of course, but the way you state it here really drives the point home. Well written.

I see somewhat of an analogy now between this and Clarke's Cradle. The theme of a very physically and abruptly changing humanity.

What I do wonder, though, is why, in this entire story, nobody ever seriously considered the option of just leaving each other be. Live and let live and all that. It seemed rather obvious to me. Three species meet, exchange what they will, and go their own separate ways. After all, morality is subjective, and any species that understands the prisoners dilemma should understand that as well. All they had to do was walk away.

I should carry a bottle of water and squirt it at anyone who disagrees with me. I will be invincible.