Kalos kagathos

Kalos kagathos (καλὸς κἀγαθός, ), sometimes written kalokagathos or kalos kai agathos, is an idiomatic phrase used in ancient Greek literature (including philosophy and historiography), attested to since Herodotus and the classical period. The phrase is adjectival, composed of two adjectives, and  (of which  is the crasis with καί, "and"). The derived noun is kalokagathia

Uses
The phrase could be used both in a generic sense, or with certain specific force. As a generic term, it may have been used as the combination of distinct virtues, which we might translate as "handsome and brave", or the intersection of the two words "good" or "upstanding". Translations such as "gentleman" or "knight" have traditionally been suggested to convey the social aspect of the phrase, while "war hero" or the more cynical "martyr" are more recent versions, and emphasise the military element.

It became a fixed phrase by which the Athenian aristocracy referred to itself; in the ethical philosophers, the first of whom were Athenian gentlemen, the term came to mean the ideal or perfect man.

kalos kai agathos, the singular balance of the good and the beautiful. "Kalos kai agathos" (handsome and good man) has a corespondent in latin: "mens sana in corpore sano" (healthy soul in healthy body). It is also used as the ideal target in balanced education of body and spirit.

Καλός
The adjective καλός encompasses meanings equivalent to English "good", "noble", and "handsome". The form given by convention is the masculine, but it was equally used of women (the feminine form is καλή) and could also describe animals or inanimate objects.

Plato, in his work Republic, used the term τό καλόν (the neuter form) in his attempts to define ideals - although it should be noted that his protagonist in the dialogue, Socrates, stated that he did not fully comprehend the nature of this καλόν.

Αγαθός
This second adjective had no particular physical or aesthetic connotations, but described a person's bravery or ethics. Again, around the 4th Century, it had become politically meaningful, and carried implications of dutiful citizenship.