Why is our first inclination to believe that we can't do things?
Is it just an excuse?
"I don't know" is a copout. I read somewhere once that when you say "I don't know" what you're really saying is "I'm not willing to grow" in this situation. It's far easier to say you don't know than to have to come up with a solution.
But when does it start being too much? If you say "I don't know" more than you provide answers, isn't that indicative of a problem?
Maybe what we believe we're saying is that if we don't know the answer to something, then we aren't obligated to figure one out. Why wasn't this situation resolved? I don't know.
I think it has to do with fear and expectation. We fear being wrong, we fear what others will think or say if we provide the truth. More than that, we want to set others' expectations low enough that we couldn't possibly disappoint them. If we dare to give an answer and it ends up being wrong, or we fail to fulfill our obligation and commitment to the answer we put forth, we will be Judged.
The truth is, we're judged either way.
Personally I'd rather be judged on my effort instead of my excuses.
EXPERIMENT: Try to notice all the times in the next week that you say "I can't" or "I don't know" and ask yourself if those answers are necessary, or how you could change them to be proactive.
I'm going to do this too. (Yay group project!!) We might all find out that we know a lot more than we're admitting to ourselves.