Full Idea
Sexual love is a desire which does not afflict virtuous men, for it is an effort to gain love resulting from the appearance of physical beauty.
Gist of Idea
Virtuous men do not feel sexual desire, which merely focuses on physical beauty
Source
report of Stoic school (fragments/reports [c.200 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 07.113
Book Reference
'The Stoics Reader', ed/tr. Inwood,B/Gerson,L.P. [Hackett 2008], p.120
A Reaction
That is a surprising interpretation of the slogan 'live according to nature'. I would have thought it was factually incorrect, since many objects of human lust rank fairly low in the scale of beauty. Sex is a tough duty if you don't desire it.