Almost everyone is familiar with the saying “it’s all Greek to me”. We use it to mean that something is utterly incomprehensible, whether it is a foreign language film without subtitles, the incoherent speech of a lunatic, or calculus.
According to World Wide Words, the phrase probably comes from the Latin phrase “Graecum est; non potest legi,” which means “it is Greek; it cannot be read.”
It was commonly used by monks translating books in medieval times. Most of them knew Latin, but not Greek. Hence, whenever they encountered Greek text, they copied it as...