Book 7
1.108
Zeno was the first to use this term καθῆκον of conduct. Etymologically it is derived from κατά τινας ἥκειν, i.e. reaching as far as, being up to, or incumbent on so and so.The ordinary meaning of the verb καθήκειν is well seen in Hdt. vii. 22 ὁ γὰρ Ἄθως ἐστὶ ὄρος μέγα τε καὶ ὀνομαστὸν ἐς θάλασσαν κατῆκον (for Athos is a great and famous mountain, reaching down to the sea). The term seems to have passed from this meaning to signify figuratively that which extends to, affects, or is incumbent on us: as near an approach, perhaps, to the idea of duty as can be expected in any ancient system of Ethics, which regards human conduct not as obedience to law, but as determination and pursuit of good. And it is an action in itself adapted to nature’s arrangements. For of the acts done at the prompting of impulse some, they observe, are fit and meet, others the reverse, while there is a third class which is neither the one nor the other.
1.108
Befitting acts are all those which reason prevails with us to do; and this is the case with honouring one’s parents, brothers and country, and intercourse with friends.
1.109
Unbefitting, or contrary to duty, are all acts that reason deprecates, e.g. to neglect one’s parents, to be indifferent to one’s brothers, not to agree with friends, to disregard the interests of one’s country, and so forth. Acts which fall under neither of the foregoing classes are those which reason neither urges us to do nor forbids, such as picking up a twig, holding a style or a scraper, and the like.
