I consider myself to be a pretty rational person, and try to avoid the cognitive pitfalls that, as a human being, I am prone to falling into. One logical fallacy that always seems to get me, no matter how much I try to banish that mode of thought, is the sunk cost fallacy.
This fallacy is the idea that you’ve already invested enough time/money/whatever into something, so to stop now would be a waste. It has its root in a number of frailties, from loss aversion to simple pride. It is a fallacy though, because how much you have invested so far in a venture has no bearing on whether that venture is going to be a success or not. If you wouldn’t have started it, it is wasteful to continue it, rather than the opposite.
Despite knowing full well the fallacious nature of it, whenever I am making a big decision, it always creeps into my head. How about you, dear readers, what logical fallacy have you had the hardest time keeping out of your mind?
Argumentum ad baculum.
Pick another one, OR I’LL KILL YOU!