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Every factual claim from every processed episode, searchable and filterable. The database grows with each new audit.
“The ancient Greeks didn't actually have a word for the colour blue.”
Current Best Understanding
The ancient Greeks did have words that covered the blue spectrum (kyanos, glaukos), but lacked a single basic colour term equivalent to the modern English 'blue.' Homer famously described the sea as 'wine-dark' (oinops). The relationship between colour terms and colour perception remains actively debated in linguistics and cognitive science (the Sapir-Whorf hypothesis). Recent work by Lazarus & Gibson (2017) suggests colour term evolution follows a universal pattern, with blue typically emerging late.
Sources
- [1] Berlin & Kay, 1969 — Basic Color Terms
- [2] Lazarus & Gibson, 2017
- [3] Guy Deutscher, Through the Language Glass, 2010
Down the Rabbit Hole
Connects to Sapir-Whorf, Homer's wine-dark sea, cross-cultural colour perception, and recent AI work on colour term learning.
“If you were bitten by a mamba, you'd be dead within about 20 minutes.”
Current Best Understanding
Untreated black mamba envenomation can be fatal, but death typically occurs between 7-15 hours after a bite, not 20 minutes. The onset of symptoms (neurological effects, breathing difficulty) can begin within 20-30 minutes, which may be the source of the confusion. Survival depends heavily on the volume of venom injected, bite location, and the victim's size. With antivenin treatment, survival rates are high.
Sources
- [1] WHO Snakebite Envenoming Guidelines, 2019
- [2] Spawls & Branch, 1995 — Dangerous Snakes of Africa
“The sky isn't actually blue — it's violet, technically. Our eyes are just more sensitive to blue.”
Current Best Understanding
Rayleigh scattering does scatter shorter wavelengths more, so violet is indeed scattered more than blue. However, the sky appears blue for multiple reasons: (1) solar radiation peaks in the blue-green range, not violet, so there's less violet light to scatter; (2) human cone cells are indeed less sensitive to violet; and (3) some violet is absorbed in the upper atmosphere. The explanation is more nuanced than 'our eyes are just more sensitive to blue.'
Sources
- [1] Young, A.T., 'Rayleigh scattering,' Applied Optics, 1981
- [2] Bohren & Huffman, Absorption and Scattering of Light, 1983
Down the Rabbit Hole
Connects back to Greek colour terms. Fascinating that the same episode touches on blue perception through both linguistics and physics.
“The moon is not the closest celestial body to the Earth.”
Current Best Understanding
This depends on what you count as a 'celestial body.' The Moon is the closest major astronomical body to Earth. However, near-Earth asteroids and meteoroids frequently pass closer than the Moon. If you count artificial satellites as 'celestial bodies' (which astronomers generally do not), thousands are closer. The QI answer appears to reference the asteroid Cruithne, sometimes called Earth's 'second moon,' but Cruithne's average distance from Earth is much greater than the Moon's. This claim is a good example of how the answer depends entirely on definitions.
Sources
- [1] NASA Near Earth Object Database
- [2] Wiegert, Innanen & Mikkola, 1997 — on Cruithne
Down the Rabbit Hole
Classification challenge: what counts as a celestial body? Connects to the broader theme of how definitions shape what we consider 'true.'
“Thomas Crapper did not invent the flushing toilet. That was Sir John Harington.”
Current Best Understanding
Correct. Sir John Harington designed and installed a flushing toilet (the 'Ajax') for Queen Elizabeth I in 1596. Thomas Crapper (1836-1910) was a real plumber who did hold patents related to bathroom fittings, but did not invent the flush toilet. His surname's resemblance to the slang term is largely coincidental — the word 'crap' predates him, deriving from Middle English/Dutch 'krappe.' Crapper did, however, popularize the siphon flush mechanism and was a successful sanitary-ware businessman.
Sources
- [1] Reyburn, Wallace — Flushed with Pride: The Story of Thomas Crapper, 1969 (though this book itself contains embellishments)
- [2] Lambton, Lucinda — Temples of Convenience, 1995
Down the Rabbit Hole
Perfect example of folk etymology and authority echo combined. The word 'crap' predating Crapper is itself quite interesting.
“There are more than 200 dead bodies on Mount Everest, and they are used as waypoints by climbers.”
Current Best Understanding
The number was approximately accurate at time of airing, but as of 2024, the estimated number of bodies on Everest exceeds 300. The claim that they are 'used as waypoints' is partially true — the most famous example being 'Green Boots,' an unidentified climber near the summit whose body served as an informal landmark for years. However, Chinese and Nepalese authorities have undertaken significant body-removal efforts since 2014, and many formerly visible bodies have been moved or covered by shifting ice. The practice of using bodies as waypoints is less common than the claim implies.
Sources
- [1] Himalayan Database, 2024
- [2] Arnette, Alan — EverestHistory.com