Prohairesis (; variously translated as "moral character", "will", "volition", "choice", "intention", or "moral choice") is a fundamental concept in the
Stoic philosophy of
Epictetus. It represents the choice involved in giving or withholding assent to impressions. The use of this Greek word was first introduced into philosophy by
Aristotle in the
Nicomachean Ethics. To Epictetus, it is the faculty that distinguishes human beings from all other creatures. The concept of prohairesis plays a cardinal role in the
Discourses and in the
Manual: the terms "prohairesis", "prohairetic", and "aprohairetic" appear some 168 times.