History is full of people who out of fear, or ignorance, or lust for power have destroyed treasures of immeasurable value which truly belong to us all. We must not let that happen again.

Carl Sagan (1934-1996) American scientist and writer

Cosmos, ep. 13 “Who Speaks for Earth?” PBS TV (1980)
    (Source)

(Source (Video); dialog verified). Referring to the destruction of the Library at Alexandria. This text is not in the Cosmos book (it would fit in roughly here).