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Start swiping — it's freeChinese characters trace back to inscriptions on Shang-dynasty oracle bones from around 1200 BC, making Chinese the oldest continuously used writing system on Earth. Unlike alphabets, each character represents a word or idea rather than a sound — a system still used by over a billion people today.
— Encyclopaedia Britannica, Chinese writing — online edition
Using the same seven tangram pieces arranged two different ways, you can build two monk figures that look almost identical — except one of them is clearly missing a foot. Both figures use every piece, with nothing left over and nothing added. How can removing a foot need no extra material?
It's an optical illusion, not a missing-material trick: the second figure's body is subtly larger, silently absorbing the exact area of the 'lost' foot, so both monks have identical total area. This is the classic tangram dissection fallacy popularized by Henry Dudeney in his puzzle collections.
Try to justify any belief with reasons, and philosopher Hans Albert argued you hit one of three walls: an infinite regress of further justifications, a circular argument that loops back on itself, or an arbitrary stopping point you just assert. Named after Baron Münchhausen, who claimed to pull himself from a swamp by his own hair, it's a central challenge in the theory of knowledge.
In 1747, aboard HMS Salisbury, James Lind took twelve sailors sick with scurvy, split them into six pairs, and gave each pair a different remedy — cider, vinegar, seawater, citrus and more — on an otherwise identical diet. Only the citrus pair recovered dramatically within days. It took the Royal Navy another 40-plus years to make citrus rations standard, but Lind's design is now considered one of the first true clinical trials.
— James Lind, A Treatise of the Scurvy — 1753 — public domain
Enron was named 'America's Most Innovative Company' by Fortune magazine six years running, while executives used off-the-books partnerships to hide mounting losses and inflate reported profits. When the scheme unravelled in late 2001, Enron collapsed into what was then the largest bankruptcy in US history, took down its auditor Arthur Andersen, and prompted Congress to pass the Sarbanes-Oxley Act overhauling corporate accounting rules.