What we actually want often diverges from what we wish we wanted.  One of the places where this conflict is clearest is in the features of others that attract us.  We are attracted to many features, including features of bodies, minds, and social networks.  We clearly put a large weight on body features, but we like to think we place more weight on other features, such as mental ones.  When we see how much we actually care about bodies we are disturbed, and perceive a conflict between what we want and what we want to want.  So why is there a conflict anyway – why are we built not to want to want what we want?

Consider that those with a better ability to distinguish a feature would naturally put more weight on that feature in when choosing.  If there is a pile of fruit and I have a short time to grab some fruit before others take them all, then if I can’t see colors well I’ll put less emphasize on colors in my choice.  After all, those who can see colors better will better be able to choose the ones with good colors.  Similarly, the better I am at distinguishing smart people, the more emphasize I’d naturally place on smarts when choosing people.

It is pretty easy for most people to tell how pretty someone is, but it is harder to tell how smart they are.  Having a high ability to tell how smart someone is says good things about you – in general it says you are pretty smart too.  And thus the fact that you put a high weight on smarts also says good things about you.  Since you have an interest in being thought well of, you also have an interest in being thought of as someone who puts a high weight on smarts. 

And serving your interests, evolution may well have arranged your mind to fool others into thinking that you put more weight on smarts than you actually do.  And this I suggest is the usual source of the conflict between what we want, and what we want to want.  We want what is useful to us, but we want to want what makes us look good to others.  We often fool ourselves into thinking that what we want to want is what we do want, and thereby also often fool others into thinking well of us.   

Note that in the case considered here, of looks vs. smarts, it is not at all obvious that what we want to want is better morally that what we actually want.  From a conversation with Katja Grace on this her birthday.