Why we surf the internet: Abi Sutherland: Return of the Dreadful Phrases: "Seneca is (dubiously) said to have told us that errare humanum est (to err is human) sed perseverare diabolicum, but to persist [in error] is diabolical...
oldster: Can I get a citation for that Seneca quote? I cannot find it. And I think it is vanishingly likely that he would use the word "diabolicum", which gets into Latin as a transliteration of New Testament Greek. So maybe he said something like "errare humanum est" somewhere, but I strongly suspect that second half comes much later than Seneca. I feel bad for being so pedantic. But then again, the "dreadful phrases" threads are natural display-cases for pedantry, so maybe it is less out of place here?
abi: Oldster, I cannot find a citation for it, but it is universally attributed to Seneca. Diabolicum is not a common Latin word, but the Greek word διαβολικός means "slanderous" or "lying". (It's also not common; I can see no references to it before the common era in Perseus. I'll amend the entry to say it's attributed to Seneca.
oldster: I'm afraid that between us we are illustrating the saying of St. Ambrosius, "to err is human, but to make a big deal pointing out other people's errors is, like, being a jerk." I'm pretty sure it was St. Ambrosius? I could be wrong. As Martin Luther said to the Pope in his 95 theses, "yeah? well, you know, that's just like, your opinion, man."
abi: Oldster, you are correct; it is Ambrosius who wrote errare humanum est, sed volgo errores aliorum indicare equidem crudelis est. It's in De Officiis Ministrorum, Book IV, De Mediis Sociabilibus.
oldster: ah, yes: the de Mediis Sociabilibus. Part of his projected summa, left incomplete at his death, de Tela Totius Terrae, vel de origine mali humani. An amazing visionary, Ambrosius! He it was who first laid down that golden precept, troglodytae non pascendae sunt...