I'm finishing up the grading of dialogue projects for my Intro course -- my major projects are quite involved and I've been headachy and tired from allergies recently, so it's been a long process -- and I have noticed that a quarter of the dialogues at some point use the phrase "let's agree to disagree," or some close variation. I'm not sure if it's just that the phrase is suddenly having a mini-vogue, or if I'm just primed to see it this round because I watched the third Men in Black movie last week, which uses the phrase several times. It's starting to wear on my nerves. Obviously there are cases where, for ethical or practical reasons, it makes sense to 'agree to disagree', but in general it's not what philosophy teachers want to hear. Let's instead agree to figure out which of us has the better reasoning, especially when writing philosophical dialogues. (In fairness, they usually seem to use it as a way of artificially bringing the dialogue to a close, and there is, of course, nothing wrong with a philosophical dialogue in which the dispute is not resolved -- excellent Platonic precedent for that.)
Of course, part of it is that I've never liked the phrase anyway; it's one of those cases of associations being colored by personal experience. I was once, years and years ago, falsely accused by someone of egregious dishonesty, and after I put forward evidence that the accusation was false, was told, "Let's just agree to disagree." At which, of course, I exploded; I would not be agreeing to disagree about whether I had been completely dishonest, thank you very much. And every time someone uses the phrase I am tempted to say, "We don't need to agree to disagree because we already are disagreeing." I think what gets me is that it's such an unbelievably low standard that almost anything would be more intellectually robust; why not agree to something more ambitiously intellectual, like swapping book recommendations, or having a temporary cooling-off period, or going to a third party for arbitration or advice, or anything else, really?
Apparently we owe this phrase to George Whitefield, although the first person we actually have on record using it is John Wesley. Thank you, Anglican-Revivalists-slash-Methodists, for this particular Totschlagargument.