I already believe this. And I feel the closest thing I have to a "meaning/purpose" is the very drive to live, which would be pointless in the eyes of an unsympathetic alien. But I don't feel depressed, just not too happy about this. And the pointlessness and horror of my existence and experience is itself interesting, the realization fun, just like those who love maths for the sake of itself as opposed to other concerns can also be very darkly intrigued by Godel's incompleteness proof, instead of losing heart. Frustrated, yes. But I would not commit suicide or wirehead myself before I understand the correct basis and full implications of this futility, especially this fear of futility. And that understanding may well be impossible, and thus my curiosity circuit will always fire, and defend me from any anti-life proof indefinitely. Could this line of reasoning be helpful to someone with depression? It's how I battled it off.
If the above is nonsense to you, I admit I am just doublefeeling. The drive, the fun and the futility are all real to me, corresponding to the wanting, liking and learning aspects of human motivation, and who am I to decide which is human's real purpose? I do not think my opinion is truth, or should be adopted. But in case there's danger of suicide from lack of point, let it be remembered that two of the three aspects can support living, whereas if you forget that the apparent futility is deep and worthy of interest, then you easily end up one against two for survival. Or is it that I am less smart and much more introspective than the average rationalist here, and thus put too little weight in the logical recursive futility and too much in the introspective curiosity and end up with this attitude, while others just survived by being truly blind/dismissive about the end of recursive justification and believe in a real and absolute boundary between motivational and evolutional justifications, like Eliezer seems to do?
Human beings are all crazy. And if you tap on our brains just a little, we get so crazy that even other humans notice. Anosognosics are one of my favorite examples of this; people with right-hemisphere damage whose left arms become paralyzed, and who deny that their left arms are paralyzed, coming up with excuses whenever they're asked why they can't move their arms.
A truly wonderful form of brain damage - it disables your ability to notice or accept the brain damage. If you're told outright that your arm is paralyzed, you'll deny it. All the marvelous excuse-generating rationalization faculties of the brain will be mobilized to mask the damage from your own sight. As Yvain summarized:
I find it disturbing that the brain has such a simple macro for absolute denial that it can be invoked as a side effect of paralysis. That a single whack on the brain can both disable a left-side motor function, and disable our ability to recognize or accept the disability. Other forms of brain damage also seem to both cause insanity and disallow recognition of that insanity - for example, when people insist that their friends have been replaced by exact duplicates after damage to face-recognizing areas.
And it really makes you wonder...
...what if we all have some form of brain damage in common, so that none of us notice some simple and obvious fact? As blatant, perhaps, as our left arms being paralyzed? Every time this fact intrudes into our universe, we come up with some ridiculous excuse to dismiss it - as ridiculous as "It's my daughter's arm" - only there's no sane doctor watching to pursue the argument any further. (Would we all come up with the same excuse?)
If the "absolute denial macro" is that simple, and invoked that easily...
Now, suppose you built an AI. You wrote the source code yourself, and so far as you can tell by inspecting the AI's thought processes, it has no equivalent of the "absolute denial macro" - there's no point damage that could inflict on it the equivalent of anosognosia. It has redundant differently-architected systems, defending in depth against cognitive errors. If one system makes a mistake, two others will catch it. The AI has no functionality at all for deliberate rationalization, let alone the doublethink and denial-of-denial that characterizes anosognosics or humans thinking about politics. Inspecting the AI's thought processes seems to show that, in accordance with your design, the AI has no intention to deceive you, and an explicit goal of telling you the truth. And in your experience so far, the AI has been, inhumanly, well-calibrated; the AI has assigned 99% certainty on a couple of hundred occasions, and been wrong exactly twice that you know of.
Arguably, you now have far better reason to trust what the AI says to you, than to trust your own thoughts.
And now the AI tells you that it's 99.9% sure - having seen it with its own cameras, and confirmed from a hundred other sources - even though (it thinks) the human brain is built to invoke the absolute denial macro on it - that...
...what?
What's the craziest thing the AI could tell you, such that you would be willing to believe that the AI was the sane one?
(Some of my own answers appear in the comments.)