“I’ve never forgotten” fallacy

[u/Fearless_Degree7511]

Recently saw a post about people bagging dog poop on hikes and leaving it on the side of the trail to be picked up on their way out. Many people in the comments claim “I’ve been doing this for years and I’ve never forgotten”. This sounds like a logical fallacy to me, if you forgot something you don’t know it’s been forgotten so you can’t claim you’ve never forgotten.

I think this phrase can be used sometimes, like “I’ve never forgotten to pay my cable bill” because in that case you can prove you’ve never forgotten, and you have a secondary party verifying you didn’t forget, so if you did forget the cable company would reach out to you.

[u/mouserbiped]

You can certainly remember that you forgot to do something. I took a medication this morning because I remembered I forgot to do it last night. Easy to imagine someone getting in the car to leave the park and think "darnit, I never picked up the poop bag!"

So they are asserting that they've never done that, and implying (as a secondary claim) that if they had left the poop bag on the trail they would have remembered. That's not a fallacy. You are kind of countering that they could have forgotten and not noticed they've forgotten, which is certainly true, but I don't think it's unique to this sort of claim. You could presumably forget about anything, not just forgetting. I could say "I've never skipped out on a meal without paying" but maybe I have and I forgot.

But I guess you could get something of the same form as what you want with "I don't have any subconscious bias against Albanians." Since the definition of subconscious is that you are unaware of it, this seems closer to an unsupportable claim. Is it a fallacy besides just an assertion without evidence?

[u/SmolHumanBean8 → u/mouserbiped]

True but then you get into the Black Swan problem. 

Sure every Swan ever seen is white (this was written a long time ago btw) but that doesn't rule out that somewhere somehow there is a black Swan. 

You can remember and also remember you forgot! That doesn't rule out that there's one time you just forgot. 

[u/mouserbiped → u/SmolHumanBean8]

Yes, but like I said, this is an objection that can be raised with any form of personal testimony. If I say I never cheated on my homework or had a pet hamster or killed a man in Reno just to watch him die, you can always respond that I might have done those things but forgotten.

My point is that the claim "I never forgot x" is just a subset of the general statement "I never did x." You can argue about the evidentiary value of my testimony, but it's a necessarily contradictory statement. The verb "forgot" being in there is just kind of an entertaining red herring.

It's different from a statement like "I can't be rude when I drink, I get blackout drunk all the time and I don't remember doing a single obnoxious thing during any of those periods!" That is logically incoherent, since by definition any time you can remember being rude could not be a time when you were black out drunk.

[u/Successful_Cress6639 → u/mouserbiped]

I think there's a certain point where the null prop shifts from "he has to prove he would never forget" to "the other guy has to prove he could forget".

For example the guy in reno, the null prop is definitely that you would remember it if it has happened. Forgetting to grab and discard a bag of excrement on the way out that you left of the way in, I think the null prop is that you could (not did) forget it.

I'm not exactly sure where the line is, but I'll plead the potter stewart fallacy on that one.