The problem with doing it by heart
The following does not appear in the Star Spangled Banner:
"Babe Ruth through the night..."
When you do something by heart, it bypasses some of the common sense processing we use to navigate our day. Of course Babe Ruth wasn't even a sparkle in Mrs. Ruth's eye during the War of 1812, but if you're singing by heart, you don't think about it.
I walked into a cheap noodle joint in Soho last month and decided I wanted tofu with vegetables. They had a little plate on display (a special, I guess) and I asked for tofu, vegetables, no sauce. The cashier pointed to the display model and said, "like this?"
I said, "with no sauce," because the gloppy stuff didn't appeal to me.
So, after asking, clearly, twice, I sat down. Four minutes later, they called my number and handed me an identical copy to the display item, oozing with fluorescent sauce.
"I was hoping that there'd be no sauce..."
She didn't miss a beat. She said, "that's the way it always comes."
She wasn't being evil. She was merely doing it by heart. Just like the intolerant judgmental guy who can quote you chapter and verse from his spiritual book of choice but never thought about the meaning of the words inside or the status quo protecting technician who isn't a scientist because she's afraid of violating something that feels like a law.
The next time you or one of your people starts rattling off the obvious truth by heart, wonder about whether it's obvious because it's true, or true because it's obvious.