Seneca

“ But if you consider any man a friend whom you do not trust as you trust yourself, you are mightily mistaken and you do not sufficiently understand what true friendship means. Indeed, I would have you discuss everything with a friend; but first of all discuss the man himself. When friendship is settled, you must trust; before friendship is formed, you must pass judgment. Those persons indeed put last first and confound their duties, who, violating the rules of Theophrastus, [2] judge a man after they have made him their friend, instead of making him their friend after they have judged him. ”

“ As to yourself, although you should live in such a way that you trust your own self with nothing which you could not entrust even to your enemy, yet, since certain matters occur which convention keeps secret, you should share with a friend at least all your worries and reflections. Regard him as loyal, and you will make him loyal. Some, for example, fearing to be deceived, have taught men to deceive; by their suspicions they have given their friend the right to do wrong. Why need I keep back any words in the presence of my friend? ”

“ It is equally faulty to trust everyone and to trust no one. Yet the former fault is, I should say, the more ingenuous, the latter the more safe. 5. In like manner you should rebuke these two kinds of men, – both those who always lack repose, and those who are always in repose. For love of bustle is not industry, – it is only the restlessness of a hunted mind. And true repose does not consist in condemning all motion as merely vexation; that kind of repose is slackness and inertia. ”