I cannot boast of much success in acquiring the reality of this virtue [(humility)], but I had a good deal with regard to the appearance of it. I made it a rule to forbear all direct contradiction to the sentiments of others, and all positive assertion of my own. I even forbid myself, agreeably to the old laws of our Junto, the use of every word or expression in the language that imported a fix’d opinion, such as certainly, undoubtedly, etc., and I adopted, instead of them, I conceive, I apprehend, or I imagine a thing to be so or so; or it so appears to me at present. When another asserted something that I thought an error, I deny’d myself the pleasure of contradicting him abruptly, and of showing immediately some absurdity in his proposition; and in answering I began by observing that in certain cases or circumstances his opinion would be right, but in the present case there appear’d or seem’d to me some difference, etc. I soon found the advantage of this change in my manner; the conversations I engag’d in went on more pleasantly. The modest way in which I propos’d my opinions procur’d them a readier recep tion and less contradiction; I had less mortification when I was found to be in the wrong, and I more easily prevail’d with others to give up their mistakes and join with me when I happened to be in the right.
From Benjamin Franklin’s autobiography:
http://xroads.virginia.edu/~Hyper/Franklin/two.html