Every part of the human brain is used for different things, so, 100% of our physical brain is in use. I think the question intended is what are we capable of, as human beings, no barrs, 100% capabillity. If all our capabillities are unleashed, this world would be VERY different. Our mere observation can change the outcome of an experiment, wow! This means the world is changed as we see it. Our involvement in the world is shaped by our minds. Our brain have more power that anyone can even begin to imagine. Self healing, telepathy, and telekenesis is just the beginning and scratches the surface of a very deep abyss. We would see the world in a completely different view and interact differently with eachother. We as human beings have such powerfull capabilities, being in complete controll of our own minds and actions, there would be no crime. There would be world peace and harmony if every person on this planet activates their true potential. There would be no greed or fighting and killing. If one person could be able to activate 100% of his or her capabilities many people would look at that person as a god because we still don't understand any of it yet, but we are getting there. Check out the new movie "Lucy" starring Scarlett Johannsonn to get a rough idea.
