To have a sixth sense is to perceive or know something without any apparent use of the ordinary five senses of sight, hearing, smell, taste and touch. Someone credited with a sixth sense seems to feel danger coming, read a room before anyone has spoken, or know who is calling before picking up the phone. In everyday use the phrase covers everything from plain intuition and well-honed professional instinct to claims of genuinely psychic ability, and it leaves it conveniently vague which of those is meant.
What’s the origin of the phrase ‘sixth sense’?
The idea that human beings have exactly five senses comes down to us from classical philosophy. Aristotle, in De Anima, treated sight, hearing, smell, taste and touch as a complete set and argued that no further sense was possible. That framework held for centuries, and it is what gives ‘a sixth sense’ its force: the phrase names a faculty over and above what nature is supposed to have issued.
When English writers first reached for it, though, it did not mean intuition. The etymologist Douglas Harper records a use from the 1690s, following the Renaissance scholar Scaliger, in which the sixth sense was titillation, the supposed sense that apprehends sexual pleasure. In 1712 William Whiston, in Primitive Christianity Reviv’d, applied the term to the foreknowledge granted to prophets, a faculty set apart from the other five in perceiving what has not yet happened rather than what has. The Oxford English Dictionary’s earliest evidence for the noun is later still, from 1761, in the writing of Laurence Sterne.
The familiar intuition meaning was thoroughly established by the early twentieth century, when novelists could deploy it without explanation. Edgar Rice Burroughs gave it a science-fiction outing in At the Earth’s Core (1914), and Joseph Conrad, in The Arrow of Gold (1919), wrote of ‘some sixth sense that men born for unlawful occupations may be gifted with’. Alongside the everyday hunch, the phrase also became the standard lay term for supposed powers beyond normal perception, and dictionaries now record ‘extrasensory perception’ as a sense in its own right.
Its most substantial modern boost came from M. Night Shyamalan’s 1999 film The Sixth Sense, in which Haley Joel Osment’s character confides to Bruce Willis’s child psychologist that he can see dead people. The film took $672.8 million worldwide, the second highest gross of any film released that year, and for a generation of filmgoers it welded the phrase to one specific meaning: perception of the supernatural. The everyday hunch sense has survived that association comfortably enough, which is more than can be said for anyone trying to count English idioms built on numbers, from at sixes and sevens upwards.