AGATHOS is ‘ideal good‘. <Kalos kagathos>, of which <kalokagathia> is the corresponding noun, is the Ancient Greek expression indicating an ideal personal behaviour. According to Werner Jaeger “it is the chivalrous ideal of a complete human personality. Therefore a personality harmonious in mind and body, foursquare in battle and speech, song and action”.

In Nicomachean Ethics and Eudemian Ethics, Aristoteles (Aristotle) uses the term <megalopsuchia> (greatness of soul).  For the scholar Jennifer Whiting (1998) it is sort of a “large scale kalokagathia”. Her interpretation depends on the notion that, for Aristoteles, <kalokagathia> and <megalopsuchia> are not virtues that come about only because people want to be respected for doing good things.

Killing a man is something ‘good’, something ‘bad’ or something neither good nor bad?
1. Maybe it is good if the person we kill is about to exterminate teens of innocent people.
2. Maybe it is bad because killing living creatures is always bad, reagardless of any motivation.
3. Maybe it is neither good nor bad if our car is hit by asteroids and kills someone as a consequence.

The notion of <agathos> as the ideal good is cardinal in Ancient Greek and Imperial Rome philosophy. The issue revolves around the ‘criteria’ for establishing the goodness of an action, a reaction, a decision. But we are all aware of the fact that these criteria vary from times to times, from people to people, from culture to culture. Therefore it is quite difficult to fix standards and assume them as perennially valid.

Nonetheless, in all times, several philosophers have considered some principles as ‘natural’ and so eternal. For instance, the prohibition to purposely cause suffering to children seems a universal criterion which applies everywhere and every time (although there are, even in this case, some rare exceptions).