Reminds me of the fallacy of humans not using 90% of their brains. In a recent Dracula novel they used a bit of handwavium in their notes about flight and supernatural powers, saying that given that we don't know what is locked up in 90% of our brains these things could be possible. No, they didn't really velieve that, it was just a lil handwavium as I said. Still. There are approx one trillion cells in your brain. 90% of those are regular old cells that do things like distribute nutrients. The remaining 10% is you, your neurons. So yes, we do only use 10% of our brain matter for thinking and such because only 10% of our brains can be used for thinking. The rest is not neurons.