Is it our bias towards optimism? (And is that bias there because pessimists take fewer risks, and therefore don't succeed at much and therefore get eliminated from the gene pool?)

I heard (on a PRI podcast, I think) a brain scientist give an interpretation of the brain as a collection of agents, with consciousness as an interpreting layer that invents reasons for our actions after we've actually done them. There's evidence of this post-fact interpretation - and while I suspect this is only part of the story, it does give a hint that our conscious mind is limited in its ability to actually change our behavior.)

Still, people do sometimes give up alcohol and other drugs, and keep new resolutions. I've stuck to my daily exercise for 22 days straight. These feel like conscious decisions (though I may be fooling myself) but where my conscious will is battling different intentions, from different parts of my mind.

Apologies if that's rambling or nonsensical. I'm a bit tired (because every day I consciously decide to sleep early and every day I fail to do it) and I haven't done my 23rd day's exercise yet. Which I'll do now.