The following points have been established:
- Moral virtue is a mean.
- It is a mean between two vices, one marked by excess and the other by deficiency.
- It is a mean in the sense that it aims at the middle point in emotions and actions.
Here are some rules for the guidance of those who seek the mean (i.e., who seek after virtue):
- Avoid the extreme most opposed to the mean for which you are seeking. One of the two extremes is always more in error than the other. If you must err from the right path, it is better to choose the lesser of two evils.
- Guard against those errors into which you are most likely to fall because of your natural inclinations by forcing yourself to move in the opposite direction. One can determine his natural inclinations by observing the amount of pleasure and pain he experiences in regard to certain things.
- Remember that you will make few mistakes if you try to avoid pleasure and pleasant things and move away from whatever is most tempting for this will tend to be the path toward the mean.
It is difficult to give any more specific guide-rules, especially where particular cases are involved. At any given time it is possible to praise someone who seems deficient in anger, and at another to praise someone who is excessively angry. There is no simple formula to determine how a man should act in a given situation or how far he can err before he is considered at fault. This difficulty of definition is inherent in all cases of perception. Questions of degree are bound up with the circumstances of particular cases. The solution in every case rests on one's own moral sensibility. But this much is clear: In all areas of human conduct the mean is most desirable and its attainment is the source of all moral virtue.
Aristotle's trinitarian doctrine of the mean has been criticized on the following grounds:
- Such an abstract mathematical formula cannot be applied to every situation.
- It would appear that most virtues have only one opposite vice and not two, and that the Aristotelian conception of extremes is artificial in this sense, especially since Aristotle occasionally has to fall back of the artifice of referring to "nameless" virtues and vices.
- That Aristotle's definitions of virtues and vices artificially narrow them in order to make them fit his formula.
- That his doctrine is primarily aesthetic rather than moral, and is based on standards of proportion and symmetry which in themselves have no ethical value.
An important point worth noting is that Aristotle's mean is not a rigid mathematical abstraction, since he points out several times that it is a "mean relative to ourselves," and differs for people of different dispositions or in different circumstances. Although his doctrines are stated abstractly. Aristotle was well aware that goodness and moral conduct cannot be reduced to artificial formulas or rules.