There is no doubt that, even in the estimation of men, talking of oneself does one harm, defeating the very end one has in view in seeking honour. It is almost universally true that whenever a man begins to talk about himself, he hurts himself with those to whom he speaks. He makes himself appear less noble and winning to them. The good things he says about himself, however true they may be, lose much of their lustre and worthiness by being proclaimed by his own lips. Self praise never can appear lovely, no matter how true it is, nor how deserving. The spirit which prompts a man to talk about himself, however it may be disguised, is really self conceit; and self conceit is not only a disfiguring blemish in a character; it is also a mark of weakness in a life. Its revealing always makes one less strong and influential with one's fellows. Instead of taking the self conceited man's own estimate of himself, people discount it so heavily that they are likely, on account of his self praise, to rate him much below his true value. Thus a man's very object in talking about himself, and proclaiming his own virtues and good deeds, is defeated. He does not receive praise of men, but dislike and depreciation instead of praise, –
Talking About Oneself, in Things to Live For