Hm. That's actually a pretty good answer. I too find I would prefer the Intellectual Porn Watcher to the Absorber. I will note, however, that the preference is rather weak. If you would give me $10 (or however much) in exchange for letting the Absorber exist rather than the Intellectual Porn Watcher, I'd take that, even for relatively low values of money. (I'm not quite sure of what the cuttoff is though, but it's low). On the other hand, I think I'd be willing to give up a fair bit of money to have the Ambitious Intellectual exist rather than the Druggie.
Thinking about it in these terms is by no means perfect, but it allows me to solidify my view of my preferences. In any case, I'll admit this is a good point.
I think the strongest reason to value certain identities over others is that otherwise, the most efficient way to create things-considered-valuable-to-us is to change who "us" is. Once we get good at AI or genetics, kill everyone and replace them with creatures who value things that are easier to manufacture than art and knowledge. Or, if we have an aversion to killing, just sterilize everyone and make sure all future creatures born are of this type. The fact that this seems absurdly evil indicates to me that we do value identity over utility to some extent.
See, "valuable" is a two place word, it takes as arguments both an object or state, and a valuer. Now, when I talk about this, I say "us" as the valuer, (and you can argue that I really should be only saying me, as our goal-systems are not necessarily aligned, but we'll put that aside), but that specifically means the "us" that is having this conversation. Or to put it another way, if you ask me "How much do you value thing X?", you can model it as me going to a black box inside my head and getting an answer. Of course, if you take out that black box and replace it with another one, the answer may be different. But, even if I know that tomorrow someone will come and do surgery to swap those "boxes", that doesn't change my answer today.
Sorry for rambling a bit. I'm not sure how best to explain it all. But I value art and knowledge. (To use your example.) If you replace me with someone who values paperclips, then that other person will go and do the things he values, like making paperclips and not art and knowledge, and I will hate him for that. I don't like the world were he does that, as my utility function does not include terms for paperclips. He would value that world, and would fight tooth and claw to get to that worldstate. Nothing says we have to agree on what is the best worldstate, and nothing says I am obliged to bring about arbitrary wold states others want.
... Oh. Actually, on reading what you wrote over again, I think (in the last section, the points about ambition still stand) we are arguing over different things, and are more in agreement then we thought. You say you value "identity over utility" (to some extent). I think I interpreted that to mean something subtly different from what you meant.
By utility, you meant total utility of everyone (or maybe the average utility of everyone?) Realizing that, of course we value lots of things over "utility", when "utility" is used in...
When someone complains that utilitarianism1 leads to the dust speck paradox or the trolley-car problem, I tell them that's a feature, not a bug. I'm not ready to say that respecting the utility monster is also a feature of utilitarianism, but it is what most people everywhere have always done. A model that doesn't allow for utility monsters can't model human behavior, and certainly shouldn't provoke indignant responses from philosophers who keep right on respecting their own utility monsters.
The utility monster is a creature that is somehow more capable of experiencing pleasure (or positive utility) than all others combined. Most people consider sacrificing everyone else's small utilities for the benefits of this monster to be repugnant.
Let's suppose the utility monster is a utility monster because it has a more highly-developed brain capable of making finer discriminations, higher-level abstractions, and more associations than all the lesser minds around it. Does that make it less repugnant? (If so, I lose you here. I invite you to post a comment explaining why utility-monster-by-smartness is an exception.) Suppose we have one utility monster and one million others. Everything we do, we do for the one utility monster. Repugnant?
Multiply by nine billion. We now have nine billion utility monsters and 9x1015 others. Still repugnant?
Yet these same enlightened, democratic societies whose philosophers decry the utility monster give approximately zero weight to the well-being of non-humans. We might try not to drive a species extinct, but when contemplating a new hydroelectric dam, nobody adds up the disutility to all the squirrels in the valley to be flooded.
If you believe the utility monster is a problem with utilitarianism, how do you take into account the well-being of squirrels? How about ants? Worms? Bacteria? You've gone to 1015 others just with ants.2 Maybe 1020 with nematodes.
"But humans are different!" our anti-utilitarian complains. "They're so much more intelligent and emotionally complex than nematodes that it would be repugnant to wipe out all humans to save any number of nematodes."
Well, that's what a real utility monster looks like.
The same people who believe this then turn around and say there's a problem with utilitarianism because (when unpacked into a plausible real-life example) it might kill all the nematodes to save one human. Given their beliefs, they should complain about the opposite "problem": For a sufficient number of nematodes, an instantiation of utilitarianism might say not to kill all the nematodes to save one human.
1. I use the term in a very general way, meaning any action selection system that uses a utility function—which in practice means any rational, deterministic action selection system in which action preferences are well-ordered.
2. This recent attempt to estimate the number of different living beings of different kinds gives some numbers. The web has many pages claiming there are 1015 ants, but I haven't found a citation of any original source.