Quick, what's 23 times 46? No time to think, your mind has already figured it out.
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Confused? No need for an explanation, your mind is two steps ahead of you.
Sometimes your brain is working so fast it's getting everything wrong. And sometimes it's working so well, it makes you blind.
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It doesn't make much sense, until ASAPScience lays it out. It all boils down to the fact that our mind is constantly playing tricks on us, but for our own good. This video explains that without a system of "slow" and "fast" thinking, our brains would be exhausted from menial tasks and we'd treat brushing our teeth like long division.
So watch the video above to learn just how smart and dumb your brain can be at the same time.
This story originally published on Mashable here.