Weakness of will

Weakness of will, or what philosophers often call by its ancient Greek name akrasia, describes actions that one takes even while personally believing, or knowing, them to be wrong. The classic puzzle about weakness of will--which remains a puzzle for philosophers to this day--is whether it is possible really to know that an action is wrong and yet commit it. Socrates is famous for, purportedly, holding the view that if one really knows a virtue, one will be virtuous in that way; and if one acts viciously, that is actually a sign of ignorance. This is an intriguing view, but it seems to be contrary to common experience: we can, it seems, knowingly be "tempted" by illicit pleasures, or to avoid virtues that cause pain.