Michael Ignatieff in the New York Times Magazine:
The philosopher Isaiah Berlin once said that the trouble with academics and commentators is that they care more about whether ideas are interesting than whether they are true. Politicians live by ideas just as much as professional thinkers do, but they can’t afford the luxury of entertaining ideas that are merely interesting. They have to work with the small number of ideas that happen to be true and the even smaller number that happen to be applicable to real life. In academic life, false ideas are merely false and useless ones can be fun to play with. In political life, false ideas can ruin the lives of millions and useless ones can waste precious resources. An intellectual’s responsibility for his ideas is to follow their consequences wherever they may lead. A politician’s responsibility is to master those consequences and prevent them from doing harm.
I’ve learned that good judgment in politics looks different from good judgment in intellectual life. Among intellectuals, judgment is about generalizing and interpreting particular facts as instances of some big idea. In politics, everything is what it is and not another thing. Specifics matter more than generalities. Theory gets in the way.