According to scientists, the bumblebees body is too heavy and its wing span too small. Aerodynamically, the bumblebee cannot fly. But the bumblebee doesnt know that and it keeps flying.

When you dont know your limitations, you go out and surprise yourself. In hindsight, you wonder if you had any limitations. The only limitations a person has are those that are self-imposed. Dont let education put limitations on you.

(Source: http://www.thelivingtreasure.com/forum/forum/forum_posts.asp?TID=1681)