The Fourth Discourse on Kingship
In the fourth Discourse Alexander the Great is represented as conversing with Diogenes, who tells him that the real king is a son of Zeus even as Homer says. Then he goes on to give the Cynic doctrine that this sonship is evidenced by qualities of mind and character, not by military power and wide dominion. He concludes by picturing graphically the spirit of avarice, the spirit of the love of pleasure, and the spirit of ambition, which rule the lives of ordinary men.
The reference at the very end to the happy fortune of those who received a good daimon or genius at their birth has led to the reasonable conjecture that this address was delivered before Trajan on his birthday, September 18th in a.d. 103.