Le Cauchemar (The Nightmare),detail, 1894
Eugène Thivier
Immortalizing sleep
paralysis. The original definition of sleep paralysis was codified by Samuel
Johnson in his 'A Dictionary of the English Language' (pub. 1755) as
"nightmare", a term that evolved into our modern definition. Such
sleep paralysis was widely considered to be the work of demons and more
specifically incubi, which were thought to sit on the chests of sleepers. In
Old English the name for these beings was mare or mære (from a proto-Germanic
*marōn, cf. Old Norse mara), hence comes the mare part in nightmare. The word
might be etymologically cognate to Greek Marōn (in the Odyssey) and Sanskrit
Māra.