Full Idea
Because animals value pleasure very little, they have not been led into sex between males or between females.
Gist of Idea
Animals have not been led into homosexuality, because they value pleasure very little
Source
Plutarch (64: Gryllus - on Rationality in Animals [c.85], 990d)
Book Reference
Plutarch: 'Essays', ed/tr. Waterfield,Robin [Penguin 1992], p.394