I recently came across the following blog post: http://jcs.biologists.org/cgi/content/full/121/11/1771, which had the following concluding paragraph:
"Focusing on important questions puts us in the awkward position of being ignorant. One of the beautiful things about science is that it allows us to bumble along, getting it wrong time after time, and feel perfectly fine as long as we learn something each time. No doubt, this can be difficult for students who are accustomed to getting the answers right. No doubt, reasonable levels of confidence and emotional resilience help, but I think scientific education might do more to ease what is a very big transition: from learning what other people once discovered to making your own discoveries. The more comfortable we become with being stupid, the deeper we will wade into the unknown and the more likely we are to make big discoveries."
To me the importance of being humble just cannot be overstated, to understand that at no point in our lives do we stop learning, implying that at no point in our lives are we the "know all".
A personel story of mine relates to this, that being that once I found myself working with bodyshop contractors in the US during the 2000 dot com boom. These guys were real knuckleheads ...the kind of developers who need guidance in writing a simple regular expression parser etc. Working with them had the strange effect on me where I became extremely overconfident. There was no problem I thought I couldnt do and no issue where I could ever be wrong. I learnt the least during this phase of my career. Then I jumped boats and joined one of the leading tech firms in the US, and was I in for a surprise. I suddenly found myself surrounded with the best minds in tech, and my confidence completely shattered. And I loved it ...it was liberating to know that there is so much to learn and so much to do.
And that experience keeps me going today too, whereby I have a large body of techy's reporting to me, when most engineers do not argue against my point of view, I know its either because I havent done my job in hiring the best minds or that I've set the wrong precedence for anticipations in such meetings.