Full Idea
Stoics say that a wise man will very rationally take himself out of life, either for the sake of his country or of his friends, or if he suffers from bitter pain, mutilation or incurable disease.
Gist of Idea
Stoics say a wise man will commit suicide if he has a good enough reason
Source
report of Stoic school (fragments/reports [c.200 BCE]) by Diogenes Laertius - Lives of Eminent Philosophers 07.1.66
Book Reference
Diogenes Laertius: 'Diogenes Laertius', ed/tr. Yonge,C.D. [Henry G. Bohn 1853], p.306