"It is right, then, to say that a person comes to be just from doing just actions and temperate from doing temperate actions; for no one has the least prospect of becoming good from failing to do them. The many, however, do not do these actions. They take refuge in arguments, thinking that they are doing philosophy, and that this is the way to become excellent people. They are like a sick person who listens attentively to the doctor, but acts on none of his instructions. Such a course of treatment will not improve the state of the sick person's body; nor will the many improve the state of their souls by this attitude to philosophy."
Nicomachean Ethics, 1105b