timelets

Contrary to popular belief, the brain is not designed for thinking. It’s designed to save you from having to think, because the brain is actually not very good at thinking.Thinking is slow and unreliable. Nevertheless, people enjoy mental work if it is successful. People like to solve problems, but not to work on unsolvable problems.
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For problems to be solved, the thinker needs adequate information from the environment, room in working memory, and the required facts and proce- dures in long-term memory.

-- Daniel T. Willingham. Why Don't Students Like School. 2009.