90% useless

Earlier this year, a movie called Lucy came out. I only saw the previews for it, so I can't comment on the film's quality. But from what I did see, the basis of the movie is that the titular character can perform amazing feats because she's using more than 10% of her brain. My first thought upon hearing that was "people still believe that nonsense?"

As has been explained countless times by people more qualified than me, and will probably have to be explained many more times, humans do not only use ten percent of their brains. We use all of our brains, same as we use 100% of our stomachs, or 100% of our eyes. We don't use it all at the same time, true, but even then, more than ten percent is used at once. You're using more than ten percent of your brain right now, as you read this. You use more than ten percent even while you're asleep.

This ten percent fallacy, while it crops up occasionally in (usually soft) Science Fiction, seems to get the most press in the realms of mystic pseudoscience. Hemp-wearing, patchouli-smelling New Age Retro Hippies from Sedona, if asked, will likely tell you that the untapped 90% of the brain contains untapped abilities that can unlock the true power of the human psyche. And then they'll try to sell you a book to read, seminar to attend, and/or herb to smoke that will help you achieve your full potential. It usually turns out that just one isn't enough, either. One has to wonder why, if they've plumbed the secrets of the cosmos, they still have to worry about crass concerns like money.

And if  you think about it, it doesn't make a whole lot of sense. Whether you believe in evolution, the Book of Genesis, aliens dropping monoliths on the planet, or whatever, why would we be walking around with organs that are 90% unused? That's extra weight we don't need slowing us down, energy our bodies need being wasted for no reason. From a purely biological sense, it would be an albatross around the neck, hindering our survival. The world simply doesn't work that way. If we really only used 10% of our brains, then our brains would be 10% of the size it actually is. That or we'd be extinct.

One last thing, there's a related idea that says if we were to use 100% of our brains, it would transform us into some sort of superman, possibly even a being of pure thought. Unfortunately for us, there is a time when the human brain is 100% active: during a seizure. And I don't think anyone would consider that to be the pinnacle of human development.

 -Long days and pleasant nights