If you're not a confident person, you shouldn't project false confidence just to impress people.

The phrase "false confidence" implies that "true confidence" exists. How do you calculate the "true" level of confidence of yourself or someone else? It's seems easy to assess a lie about career, wealth, or age... but how do we test the truth value of a display of confidence?

Your view of the social world and ethics seems different from mine. We've had discussions on the topic of "fake it 'til you make it" on LW before, and you might be interested in these comments:

http://lesswrong.com/lw/13j/of_exclusionary_speech_and_gender_politics/1vay?c=1 http://lesswrong.com/lw/2tw/love_and_rationality_less_wrongers_on_okcupid/2sox http://lesswrong.com/lw/2tw/love_and_rationality_less_wrongers_on_okcupid/2snu