One of the Cognitive ghosts discussed in the The Rest Is Science episode “Cognitive Ghosts”.
What it is
Not every cognitive ghost lives inside one skull. The episode widens the idea to cultural ghosts: beliefs, instincts, and customs that survive long after the reason that created them has vanished — “echoes of our historical past” carried forward in stories, habits, and screens. They’re collective misfires: the cultural equivalent of the brain filling a gap with a confident-but-wrong answer.
Superstitions that outlived their reasons
- Spilling salt is bad luck. Salt was once enormously valuable — vital for preserving food, even used as payment (salary shares the root). Spilling it really was a costly disaster. The practical reason has long dissipated, but the dread — and the “throw a pinch over your left shoulder at the devil” remedy — lingers.
- Amethyst prevents drunkenness. The name comes from Greek améthystos, “not intoxicated”. The episode tells the tale of wine goblets carved from (or coloured like) amethyst, which could disguise water as wine — letting, say, a Roman official appear to drink with everyone while staying sober. The myth of the stone’s sobering power outlived the trick.
Screen-tropes that rewired our expectations (“the coconut effect”)
Fiction trains us to expect a fake version of reality, and then reality has to live up to the fiction:
- Coconuts for horse hooves — the classic radio/Foley trick (immortalised by Monty Python); real hoofbeats often don’t “read” as convincing, so the fake sound is the expected sound. This is the namesake of the “coconut effect.”
- Electrocution showing the skeleton through the skin — pure cartoon physics.
- Distinct clicks and racks when drawing a gun — added for drama; most don’t make those sounds.
- Secret Service agents touching their earpieces — largely theatrical signalling of “I’m on duty”.
- Swearing in period pieces (e.g. Deadwood) — written with modern taboo words because the genuinely shocking oaths of the era would land as quaint to us.
“We now need to keep the lie up, because otherwise they will be confused… we’re so divorced from it.”
References from the show
- The hosts frame these as ghosts of oral history — superstitions as “the oral history of something that really used to scare our ancestors” — and connect screen-tropes to the TV Tropes “coconut effect” idea (a special effect or convention kept because audiences now expect the inaccurate version).
Links
- The Coconut Effect — TV Tropes
- Why is spilling salt considered bad luck? — History
- Amethyst — etymology & the “not drunk” myth (Wikipedia)
Related
- Hypnic jerk — a biological vestige that outlived its purpose, the bodily counterpart to these cultural ones
- Cognitive ghosts