Whatever the percentage, most of our talking comes with predefined scripts that happen automatically. For example: when I'm at the store and check out, the cashier should tell me to "Have a nice day." In which I reply, "You, too." I don't even have to think of a response; it just happens. My brain actually hears Charlie Brown's teacher, and issues the generic statement when there's silence. I know this routine because it happens every single time I go shopping.
Except when some rebellious ne'er-do-well mucks up the whole shopping experience. I just paid $68.35 for some printer ink and wiper fluid, received my receipt, and ready myself for a hearty "You, too." But instead of hearing "Have a nice day," I hear, "Thanks for shopping with us." That's not part of the plan!
My brain already heard the silence and blurted out the "You, too." But that makes no sense. She didn't go shopping. I went shopping. And even if she did happen to go shopping, it was with me. "You, too" sounds like she just bought a watch out of my trench coat. Or, perhaps I'm some crazy man who thinks he's actually the cashier. What am I doing with her groceries? And where is her change?
I can't take it back, because she already started ringing up the twenty-seven Power Bars that the dude in back of me needs. What am I going to say, anyways, that would warrant such an interruption.
"Uh...excuse me miss. When I said 'You, too,' I thought you said 'Have a nice day.' In fact you said, 'Thanks for shopping with us.' These two sentences sound nothing alike, but since I'm such a poor listener, I blurted out something completely nonsensical at the time. I guess I should have said 'You're welcome' or 'No problem' or something like that, but I didn't. I just want to clarify my position on the whole conversation thing that just happened. So...have a nice day?"That would probably get me escorted out by security. Or beaten up by the bag boy who thinks he's her boyfriend, even though they've only spoken once outside of work. Or scowled at by a line of angry shoppers who also can't figure out how to use the U-Check.
Instead, I'll just slink away with my head slumped low and my pride bruised. I'll try to convince myself that nobody noticed, but I know an awkward silence when I hear it. We both know what happened, and there's no rectifying it. That conversation will just have to eat away at me for 37 years until I have an aneurysm in my sleep.
Plausible, since I hear that 74% of all non-conversational screw-ups lead to death. At least I think I heard that.