Memory errors have a bearing on rationality because you need accurate data to think about, and one of the primary causes of not remembering something is not having noticed it.
I can say my name twice, spell it, and show people a business card, and still have them get it wrong.
If you want more about how little people perceive, I recommend Sleight of Mind, a book about neurology and stage magic.
If it's worth saying, but not worth its own post (even in Discussion), then it goes here.
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3. Open Threads should be posted in Discussion, and not Main.
4. Open Threads should start on Monday, and end on Sunday.