Fallacies: L (Part 1 of 2)

Core idea

The first run of L entries is dominated by claims that feel like settled knowledge — printed in encyclopedias, sung in nursery rhymes, taught by parents — and turn out to be wrong. Lemmings do not march off cliffs in mass suicide. The Leaning Tower of Pisa was not designed to lean; it leans because its foundation was botched. Lefthandedness is not unnatural. Being lactose intolerant is not the rare condition most Westerners assume — worldwide, it is the norm. In each case the misconception is widely shared, confidently stated, and easily checked.

The topic's quiet argument is that authority is not evidence. An entry in the Encyclopedia Britannica claimed lemmings drowned themselves; a respected historian, Arnold Toynbee, repeated travellers' tales about West African languages that had no basis in fact. If the best-credentialled sources pass on legends, then the reader cannot outsource judgment to a famous name. Verification has to happen at the level of the specific claim.

Why it matters

These fallacies show how a vivid story crowds out a dull truth. "Lemmings commit suicide" is a gripping image; "lemmings sometimes disperse when food runs short, and a few drown crossing water" is not. The dramatic version spreads, gets filmed, and becomes a synonym for blind crowd behavior. Meanwhile the Leaning Tower is admired as a feat of design when it is really a monument to a builder's incompetence — flattery quietly rewriting failure as genius.

There is also a moral cost. Calling lefthandedness "unnatural" rests on two ugly fallacies — that whoever differs from me must be wrong, and that the majority is always right. Debunking it is not trivia; it dismantles a prejudice. And the lactose entry matters because assuming a Western minority condition is the human default can mislead nutrition advice for most of the planet.

Key takeaways

Mental model

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Practical application

The habit to take from this batch is treating "an encyclopedia says so" as a starting point, not a verdict. When the lemming myth sat in a reference work, it lent itself authority it had not earned. A claim's prestige tells you who repeated it, not whether it is true.

Example

Picture a documentary clip of thousands of small animals pouring over a cliff edge, narrated as instinctive self-destruction. Apply the L topic's test. First, ask whether the story is too satisfying — and "mindless crowd kills itself" is a perfect parable, which is a warning sign. Second, ask who first reported it and how. The cliff footage from one famous nature film was, it later emerged, staged. Third, ask what the dull explanation is: lemmings simply spread out to find food, and a few misjudge a stretch of water. The myth endured because a tragic, meaningful image will always travel faster than an accurate, boring one.

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