My friend Tauriq Moosa, on his blog Against the New Taboo, makes a compelling argument against the notion that happiness can or should be our only goal in life:

We’re told to have a positive attitude; that love conquers all; that anger is unhelpful and hate unneeded. Evangelists of optimism would drown us in their toothy smiles and keep us as drones on the front line of the happiness assault. This, however, is wrong.

To take this approach is not only so often naïve, but terribly mistaken (and insulting). It forces a response that might not only be inappropriate but immoral to the current situation, forcing a pastiche of black-and-white simplicity onto a reality more complex than implied by such positive attitudes.

Moosa might not have been realized this, but his argument has far-reaching implications, the most obvious of which to me is that utilitarianism — the proposition that we should work to maximize happiness and reduce suffering — is at best our broadest ethical outlook, and at worst our vaguest and most meaningless.