Phronesis (Greek: ????????) in Aristotle's Nicomachean Ethics is the virtue of moral thought, usually translated "practical wisdom", sometimes as "prudence".Aristotle distinguishes between two intellectual virtues: sophia and phronesis. Sophia (usually translated "wisdom") is the ability to think well about the nature of the world, to discern why the world is the way it is (this is sometimes equated with science); sophia involves deliberation concerning universal truths. Phronesis is the ability to think about how and why we should act in order to change things, and especially to improve one's own life. Aristotle says that phronesis is not simply a skill, however, as it involves not only the ability to decide how to achieve a certain end, but also the ability to reflect upon and determine that end (this latter point is denied by some commentators, who contend that Aristotle considers the desired end, eudaimonia, to be given, such that phronesis is merely the ability to achieve that
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http://en.wikipedia.org/wiki/Phronesis