We only realize how much of the brain is busy lying to us when we catch it doing a bad job of it. My favorite is when I only catch a partial glimpse of some words and my brain tells me, with a joyous certainty, that it says something ridiculously improbable. But your brain is doing that all the time, just usually better than that. I heard one neurologist I like (I suspect VS Ramachandran, but my brain may be lying to me) talk about how your brain is a parliment and it had lots of subcommittees and you only get to see the bills that passed and, just like real politics, there's a lot of lying, scheming, and behind the scenes nonsense going on. It doesn't matter what the truth is, this is what gets us re-elected. And the voting system is rigged.