I'm a little tired of "X is a fallacy." Everything is a fallacy, or nearly so. Almost every method by which we naturally and intuitively reason have been shown to be error prone, deeply biased, or at best an approximate heuristic. This is why Wikipedia is able to list a hundred different kinds of fallacies[1] without even beginning to scratch the surface. I'm not a huge fan of teaching rationality by exhaustively listing fallacies because it's endless. But when maintaining a blacklist becomes too onerous, the solution is to switch to a whitelist. This turns out to be much easier, because the constructive list of techniques that work is very short. Of all the ways of reasoning that are intuitive appealing and naturally make sense to us, only two have stood the test of time:
1. Modus Ponens (If A implies B, and also A, then B.)
2. The Hypothetico-deductive model (The guess-and-check scientific method)
And frankly I'm a little suspicious of that second one!
These are better known as "math" and "science," or "deduction" an "induction." And yes, modus ponens is really the only inference rule you need for logic - Hilbert proved that[2].
The other 98% of the algorithms built into our brains are unreliable and cannot be trusted. Consider for example your optical cortex, which is attempts to patch up raw input in a dozen different ways, resulting in dozens of optical illusions, saccadic masking, not being aware of your own blindspot, and so on. We literally can't trust our eyes... or rather, we can't trust the instinctive processing our own brains do on raw visual input. So it is with the other parts of our brain. Or what Kahneman calls "System 1."[3] It's a patchwork of barely functional heuristics.
Scientists learn to shut out that 98% and use only the two reliable systems. Mathematicians take it even further and shut out 99%, leaving only modus ponens and methods of deduction.
People hate that this is true. They want to reason intuitively, naturally. They hope they can patch their hopelessly bugged brains into something useful if they can just memorize and avoid a list of pitfalls. I'm telling you there's a better way. Forget about fallacies. Stop looking for shortcuts like "mental models." Construct rigorous arguments inside of formal deductive systems. Use those to build formal mathematical models that describe reality. Test those models ruthlessly against experimental data, even to destruction.
You know this works. It put a man on the moon, for god sake. It predicted what a black hole would look like, then took a picture of it. It's cured so many diseases and so many problems that our main problem is that we don't have enough problems. Yet people still want to look for shortcuts. I can sympathize with that. We're all busy. But the real choice you face is this: be rigorous, or be wrong a lot.
1. Modus Ponens (If A implies B, and also A, then B.)
2. The Hypothetico-deductive model (The guess-and-check scientific method)
And frankly I'm a little suspicious of that second one!
These are better known as "math" and "science," or "deduction" an "induction." And yes, modus ponens is really the only inference rule you need for logic - Hilbert proved that[2].
The other 98% of the algorithms built into our brains are unreliable and cannot be trusted. Consider for example your optical cortex, which is attempts to patch up raw input in a dozen different ways, resulting in dozens of optical illusions, saccadic masking, not being aware of your own blindspot, and so on. We literally can't trust our eyes... or rather, we can't trust the instinctive processing our own brains do on raw visual input. So it is with the other parts of our brain. Or what Kahneman calls "System 1."[3] It's a patchwork of barely functional heuristics.
Scientists learn to shut out that 98% and use only the two reliable systems. Mathematicians take it even further and shut out 99%, leaving only modus ponens and methods of deduction.
People hate that this is true. They want to reason intuitively, naturally. They hope they can patch their hopelessly bugged brains into something useful if they can just memorize and avoid a list of pitfalls. I'm telling you there's a better way. Forget about fallacies. Stop looking for shortcuts like "mental models." Construct rigorous arguments inside of formal deductive systems. Use those to build formal mathematical models that describe reality. Test those models ruthlessly against experimental data, even to destruction.
You know this works. It put a man on the moon, for god sake. It predicted what a black hole would look like, then took a picture of it. It's cured so many diseases and so many problems that our main problem is that we don't have enough problems. Yet people still want to look for shortcuts. I can sympathize with that. We're all busy. But the real choice you face is this: be rigorous, or be wrong a lot.
[1]: https://en.wikipedia.org/wiki/List_of_fallacies
[2]: https://en.wikipedia.org/wiki/Hilbert_system
[3]: https://en.wikipedia.org/wiki/Thinking,_Fast_and_Slow