Our brain size relates more to proportion than it does to intelligence. Our brain is smaller than a whale’s because our body is smaller. Still, your brain is structured in a way that enables you to survive and succeed. So would you believe that humans only use 10% of their brains instead of 100%?
If you want to understand it better I advise you to watch "LUCY". It’s one of the best movies. This movie talks about the capability of our brain when you use it completely.
We can notice 7 things that could happen if the potential our brains increased: