Found in 1 comment on Hacker News
zamalek · 2016-08-03 · Original thread
"I don't know," one of the hardest three letter sentences to say in English[1], one of the most important to say, as well as one of the most rewarding (time to learn).

I don't think it's about a lack of confidence, it's just awareness about how far your knowledge extends and honesty surrounding that.

[1]: http://www.amazon.com/dp/0062218336

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