A well-known May 1968 slogan reads: "Be realistic, demand the impossible!" Is that just an affected Parisian provocation, or does it contain a useful insight? Suppose you've every reason to believe that your political dreams are unachievable. Your ideals yield prescriptions--things we ought to try to bring about--that just won't happen. Not now, not anytime in the foreseeable future. Or maybe your ideals don't even lead to prescriptions: perhaps all they tell you is that the status quo is rotten and ought to be replaced by something else, though you don't know what. But the question is, as they say, academic, since the revolution isn't happening anyway. If that's what your political ideals tell you, what should you do about it? And does thinking in that way make you a political failure?

To avoid answering the latter question in the affirmative, most philosophers would answer the former in one out of two ways. The first answer is to say that, well, you should revise your ideals, for they fail to latch onto politics in the right way. The second answer tells you to think of your ideals as merely regulative: they give you an indication of a general direction, rather than a political programme. Radicals are unlikely to be happy with either answer. The first one is just an encouragement to abandon radicalism in the face of the political odds. The second one makes it hard to envision the ultimate political import of one's radicalism: is my radical politics just a fantastical wish list? Yet those two answers may not exhaust the options available to us. Theodor W. Adorno, the stern patriarch of post-war Frankfurt School critical theory can provide us with a third answer, and one that's more appealing to radicals of an uncompromising sort. Or, some would say, to academic solipsists who don't want to get their hands dirty with real politics -- you be the judge.