Pythagorean Cup: the 2,500-Year-Old Practical Joke

Typically attributed to 6th Century B.C. Greek mathematician and philosopher Pythagoras of Samos, the Pythagorean or "Greedy" Cup works like a normal cup when filled up to an inscribed line, but drains its contents when overfilled - teaching the user a lesson about overindulgence. The cup works via the principle of the siphon, a channel that allows fluid to be transferred from a higher elevation to a lower one while passing through an even higher point. While siphons have been used for thousands of years, the physics of their operation are more complex and mysterious than they might appear, and have been the subject of much experimentation and scientific debate - even up to the present day. SOURCES: https://www.ncbi.nlm.nih.gov/pmc/arti... https://web.archive.org/web/201307290... https://www.phys.uhh.hawaii.edu/docum... http://hawaii.edu/news/article.php?aI... https://commons.wikimedia.org/w/index... https://www.ncbi.nlm.nih.gov/pmc/arti... https://www.sifouniospottery.com/pyth... https://www.ancient-origins.net/news-... https://davidson.weizmann.ac.il/en/on... http://www.romanaqueducts.info/siphon... https://eprints.qut.edu.au/41923/1/Th... https://iopscience.iop.org/article/10...