Let me propose a thought experiment that might dissuade those who speak of self-choice as the ultimate value. Suppose it were possible, through some sort of instantaneous genetic engineering, to change any aspect of your nature, so that you could have any combination of capacities that has ever been within the range of human possibility: you could have Michael Jordan's fade-away shot, Mozart's musicality, Groucho Marx's comic gifts, Proust's delicate way with language. Suppose you could put these together with any desires you wanted--homo- or hetero-, a taste for Wagner or Eminem. (You might saunter into the metamorphosis chamber whistling the overture to Die Meistersinger and strut out murmuring "Will the Real Slim Shady Please Stand Up?) Suppose, further, that there were no careers or professions in this world because all material needs and services were met by intelligent machines. Far from being a utopia, so it seems to me, this would be a kind of hell. There would be no reason to choose any of these options, because there would be no achievement in putting together a life. One way of this life would be meaningless comes from Nietzche:
One thing is needful.-- To "give style" to one's character-- a great and rare art! It is practiced by those who survey all the strengths and weaknesses of their nature and then fit them into an artistic plan until every one of them appears as art and reason and even weaknesses delight the eye. Here a large mass of second nature has been added; there a piece of orginal nature has been removed-- both times through long practice and daily work at it. Here the ugly that could not be removed is concealed; there it has been reinterpreted and made sublime.
--Kwame Anthony Appiah from The Ethics of Identity