Robert Burton, Anatomy of Melancholy
, Part. I, Sec. 2, Mem. 3, Subs. 10:
And which is worse, as if discontents and miseries would not come fast enough upon us: homo homini daemon, we maul, persecute, and study how to sting, gall, and vex one another with mutual hatred, abuses, injuries; preying upon and devouring as so many ravenous birds; and as jugglers, panders, bawds, cozening one another; or raging as wolves, tigers, and devils, we take a delight to torment one another; men are evil, wicked, malicious, treacherous, and naught, not loving one another, or loving themselves, not hospitable, charitable, nor sociable as they ought to be, but counterfeit, dissemblers, ambidexters, all for their own ends, hard-hearted, merciless, pitiless, and to benefit themselves, they care not what mischief they procure to others.
"Homo homini daemon" ("man is to man a devil") says Burton, adapting Plautus, Asinaria
495 ("lupus est homo homini" = "man is to man a wolf"). Cf. Sartre, "Hell is other people" ("L'enfer, c'est les autres").