Meno: I often wonder, Socrates, that Gorgias is never heard promising to teach virtue: and when he hears others promising he only laughs at them; but he thinks that men should be taught to speak.
-- Plato, Meno (trans. Benjamin Jowett)
One of the main criticisms of the Sophists was that they would teach individuals to argue without absolute reference to the "moral" nature of the argument. The problem of course is that the Sophists were partly right - choices, political or otherwise, are often difficult to make and in part this is because choices don't as often as as we would like present clear alternatives. Furthermore, the basis of these alternatives are never going to be as concrete as we would like. That doesn't mean that one should be a radical skeptic (though if that is what floats your boat, go for it - from my experience it leads to yawning nihilism, a state which has its definite costs as well as benefits), but it should make moderate skepticism seem at least attractive.