Martin Gardner’s 1975 April Fools Hoax: The Greatest Scientific Troll in Mathematics

How Martin Gardner Pulled Off the Ultimate April Fools Math Hoax

April 1, 1975. Exactly 50 years ago, Martin Gardner — the world’s most famous popularizer of mathematics — decided to play a prank. He orchestrated what may be the largest single act of scientific trolling in the history of mathematics, if not the entire century.

On that day, the April issue of Scientific American ran the latest installment of Gardner’s beloved column “Mathematical Games.” But this one was different. Disguised as a serious piece of science journalism, Gardner presented six supposedly groundbreaking discoveries, each one teetering on the edge between genius and absurdity. Here is what he told the world.

Six Fake Discoveries at the Heart of the Martin Gardner April Fools Hoax

1. The Four Color Conjecture — Disproved!
Graph theorist William McGregor of New York had allegedly found a map of 110 regions that cannot be colored with just four colors. This was one of the most famous open problems in combinatorics, with mathematicians having struggled to prove it for nearly a hundred years. Gardner’s column announced that a full proof of the refutation would be published in 1978. Naturally, nothing of the sort ever appeared — the conjecture was actually proved (not disproved) the very next year, in 1976, by Kenneth Appel and Wolfgang Haken using a computer.

2. e^(π√163) Is an Exact Integer
Gardner claimed that one John Brillo had proven that the expression e^(π√163) equals the exact integer 262,537,412,640,768,744. This one is deliciously close to the truth: the value of that expression is extraordinarily close to a whole number — but not quite. The phenomenon is connected to deep theory involving modular forms and so-called “almost integers,” a curiosity that continues to fascinate mathematicians today.

3. The Move P-KR4 Wins Every Chess Game
A computer called MacHic, built at MIT’s Artificial Intelligence Lab (a reminder of just how ancient AI research really is), had allegedly spent seven months playing chess against itself and “proved” that the pawn move to g4 guarantees a win for White. Gardner wrote that the discovery had thrown grandmasters into a panic, that Kissinger and Brezhnev were preparing a summit over it, and that Bobby Fischer was demanding $25 million for a match against the machine. It was a pitch-perfect parody of the hype surrounding AI and chess engines — and, frankly, it feels remarkably familiar today.

4. Special Relativity Is Wrong
Gardner described a thought experiment that supposedly revealed a logical contradiction in the Lorentz transformations. In reality, it was a textbook pseudo-paradox designed to mislead an inattentive reader. The joke demonstrated how effortlessly even educated audiences can be confused by elegant-sounding sophistry.

5. Leonardo da Vinci Invented the Flush Toilet
A “lost page” from the Codex Madrid I had been discovered, depicting a prototype toilet complete with a valve mechanism — proof, apparently, that Leonardo got there before Thomas Crapper. Gardner was mocking the media’s weekly habit of uncovering yet another forgotten act of Leonardo’s genius.

6. A Psychic Motor Powered by Thought
A paper cylinder that rotates using the power of your aura. All you need is silence, a north-south orientation, and the force of your mind. The device’s inventor was listed as one Dr. Ripoff, assisted by a Miss Birdbrain. Assembly instructions were included.

Why This Martin Gardner April Fools Joke Still Matters

What Gardner did was far more than a prank. He demonstrated, with surgical precision, how easily science and pseudoscience blur together in the public mind. How the media chases sensation and loses rigor. And how critical thinking can collapse in the face of a claim that merely sounds mathematical.

The deeper irony is that in the years following, nearly every one of these fake discoveries — with the possible exception of the psychic motor — was seriously discussed by someone, somewhere. Some of them still are.

That is the mark of a truly great hoax: it reveals something true about human credulity precisely by being false.