Famously, Epictetus had an exchange with someone on the necessity, credibility and utility of logic: DISCOURSESCHAPTER XXV How is logic necessary? When someone in [Epictetus’] audience said, Convince me that logic is necessary, he answered: Do you wish me to demonstrate this to you?—Yes.—Well, then, must I use a demonstrative argument?—And when the questioner had agreed to that, Epictetus asked him. How, then, will you know if I impose upon you?—As the man had no answer to give, Epictetus said: Do you see how you yourself admit that all this instruction is necessary, if, without it, you cannot so much as know whether it is necessary or not? [Cf J. C. Wright] However, many today miss the point. J C Read More ›

Everything below is from a comment posted by UB: Ed at 34, [re: Ed on telling the truth]It is just one of the rules we have to follow if we want to be welcome in society. If I chose to live by myself in a cabin in the hills I would have no obligation to be honest to the rare person that stumbled upon me. Yes, you’ve been very concise on this feature of your belief system, and we understand you. If you live in a society then you have to tell the truth as a moral obligation to the consensus of that society (who collectively believe that people should tell the truth). But if you live out on your own, then Read More ›