For at least two thirds of our miseries spring from human stupidity, human malice, and those great motivators and justifiers of malice and stupidity, idealism, dogmatism, and proselytizing zeal on behalf of religious or political idols.

Aldous Huxley (1894-1963) English novelist, essayist and critic
“Knowledge and Understanding,” Vedanta and the West (May-Jun 1956)
    (Source)

Revision of a 1955 lecture given at the Vedanta Society of Southern California; this phrase, however, does not occur in it (the surrounding text is found around the 10:00 mark). Reprinted in Adonis and the Alphabet, and Other Essays (in the US Tomorrow and Tomorrow and Tomorrow, and Other Essays) (1956).