Seneca, Moral Epistles 94.17
“This part of precepts should be tossed away because it can’t give to everyone what it guarantees to a small few. Wisdom, however, welcomes all. There’s no difference, really, between the popular madness in general and the kind that requires medical treatment except that the individual suffers from a disease and the masses are afflicted by false opinions. For one, the symptoms of insanity develop from poor health, the other arises from sick minds.
If one offers maxims to a madman about how to speak, or walk, or how to act in public and private, they’d prove to be crazier than the one they’re advising. Someone really needs to treat their black bile and remove the initial cause of the affliction. This is what is required for a diseased mind too. The madness needs to be shed first, otherwise all your words of warning are useless.”
“Ergo ista praeceptiva pars summovenda est, quia quod paucis promittit, praestare omnibus non potest; sapientia autem omnes tenet. Inter insaniam publicamet hanc, quae medicis traditur, nihil interest nisi quod haec morbo laborat, illa opinionibus falsis. Altera causas furoris traxit ex valitudine, altera animi mala valitudo est. Si quis furioso praecepta det, quomodo loqui debeat, quomodo procedere, quomodo in publico se gerere, quomodo in privato, erit ipso, quem monebit, insanior. Ei bilis1 nigra curanda est et ipsa furoris causa removenda. Idem in hoc alio animi furore faciendum est. Ipse discuti debet; alioqui abibunt in vanum monentium verba.”