Conceit is the most contemptible and one of the most odious qualities in the world. It is vanity driven from all other shifts, and forced to appeal to itself for admiration.

Someone loudly admiring themselves is usually someone who has run out of other sources. Vanity prefers to be fed from outside, and when the outside stops supplying it, the person turns inward and starts doing the job alone, which is why conceit is so grating and also faintly sad. What looks like an excess of self-regard is often a shortage of regard from anyone else.

When you meet it, you can decline to be impressed without being cruel about it. And when you catch yourself listing your own merits, even silently, ask what you were hoping someone would have said. Then consider asking for it directly instead.