Aristotle: Nicomachean Ethics
Do we deliberate about the ends or means of our moral actions?
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Aristotle says that we only deliberate about the means of our moral actions, not our ends. To illustrate this point, Aristotle gives the example of a doctor, who is much more interested in finding out how to heal a patient than whether to heal a patient. The latter end is simply assumed in the process of deliberation.
Aristotle, Nichomachean Ethics, Book III