Moral Letters to Lucilius [Epistulae morales ad Lucilium], letter 3 "On True and False Friendship" [tr. Gummere] - Seneca the Younger | WIST Quotations
It is equally faulty to trust everyone and to trust no one. [Utrumque enim vitium est et omnibus credere et nulli.] Alt. trans.: "For it is both a vice to believe everyone and no-one."
