Arthur Koestler The Sleepwalkers Page 37

in orphic usage, theoria came to signify "a state of fervent religious contemplation, in which the spectator is identified with the suffering god, dies in his death, and rises again in his new birth". As the Pythagoreans canalized religious fervour into intellectual fervour, ritual ecstasy into the ecstasy of discovery, theoria gradually changed its meaning into "theory" in the modern sense.