This quote comes from my mother-in-law's church bulletin, author unknown:
"May God bless you with enough foolishness to believe that you can make a difference in this world, so that you can do what others claim cannot be done."
Every single one of us DOES make a difference in the world. We would not bother coming here if that were not the case. So yes, let's have the foolishness to put ourselves to good use! Do you have the confidence, courage, and persistence to try new things, or do you live in fear of failure or of what others may think of you?
There's an element of joy and fun in "foolishness"--it truly is an adventure to push yourself beyond what you think are your limits. Those personal limits don't actually exist--we can always do at least a bit more than we think we can.
I can think of lots of things that others claimed could not be done: people flying, a man on the moon, cures for various diseases, portable phones, and so on. What great idea is lying within you? Do us all a favor and let your foolishness shine!