Selected Criticisms of Aristotle's Ethics

"as guidance about what is the good life, what precisely one ought to do, or even by what standard one should try to decide what one ought to do, this is too circular to be very helpful. And though Aristotle's account is filled out with detailed descriptions of many of the virtues, moral as well as intellectual, the air of indeterminacy persists. We learn the names of the pairs of contrary vices that contrast with each of the virtues, but very little about where or how to draw the dividing lines, where or how to fix the mean. As Sidgwick says, he "only indicates the whereabouts of virtue.""