Fallacies: S (Part 4 of 4)

Core idea

The final stretch of S is dominated by health and history folklore: sugar blamed for crime, swimming after lunch declared deadly, syphilis pinned on the New World. Several of these myths share a single faulty move — mistaking correlation for cause, or mistaking a confident-sounding mechanism for proof. The corrective is to ask whether the proposed cause is the only explanation, or merely the most dramatic one.

Key takeaways

Why it matters

Health folklore is sticky because each myth offers a single, memorable villain — sugar, corn syrup, a tight waistband. Reality is usually a matter of dose, context, and several causes at once. Spotting the "single dramatic villain" shape is half the work of debunking it.

Mental model

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Practical application

When a food or habit is named as the cause of a problem, ask three things: Is there a controlled comparison, or just two trends side by side? Is the effect about quantity rather than the substance itself? Has the name simply been applied recently, hiding older cases? Sugar, corn syrup and syphilis each fail one of those checks.

Example

A wellness post claims a particular oil "causes inflammation" because inflammation rose in a population that ate more of it. Run the checks: was there a controlled trial, or just two rising lines? Inflammation tracks dozens of dietary and lifestyle factors at once — this is the sugar-and-crime fallacy wearing a nutrition label.

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