We know hate's been around for a long time because it's mentioned in texts that date back for centuries. Hate is mentioned in the Book of Genesis and in Indian Vedic scripture [source: Tuske]. The ancient Greeks also contemplated its meaning. Fourth century B.C. philosopher Diogenes Laertius defined hate as "a growing or lasting desire or craving that it should go ill with somebody," and included it among the irrational urges that plagued humankind [source: Diogenes].
The ancients often acted upon their animosity. In the second century B.C., the great Carthaginian general Hannibal pledged to his father eternal hatred against the Romans, who had seized valued provinces from Carthage [source: Lendering]. Hannibal made good on that by invading Italy. But the Romans responded even more venomously. In 146 B.C., they set out to wipe the hated Carthaginians off the face of the Earth, burning down the city's houses as their trapped inhabitants screamed for help [source: BBC].
Hatred was condemned by most of the world's holy scriptures, from the fifth century B.C. Buddhist Dhammapada and the Christian New Testament to the Islamic Koran, which admonishes believers to "let not hatred of a people incite you not to act equitably" [sources: Medieval Sourcebook]. The Muslim Turks behaved similarly hatefully when they sacked the Byzantine Christian capital of Constantinople in 1453, according to the eyewitness account of Nicolo Barbaro, a Venetian physician. He wrote that "anyone [the Turks] found, they put to the scimitar, women and men, old and young, of any condition" [source: Barbaro].
Even in peacetime, it was so common in Medieval and Renaissance Europe to hate others that there was a legal term for it, inimicitia (Latin for "unfriendship") [source: Gibson]. In Italy, such extreme resentments evolved into a custom called the vendetta, in which a person's kinsmen and descendants were obligated to seek vengeance, no matter how long it took [source: Dean].
Despite attempts to ban the vendetta, it persisted and gradually even took root in America. In West Virginia in the late 1800s, a dispute over the alleged theft of a pig mushroomed into a bloody feud between the Hatfield and McCoy families that claimed nearly a half-dozen lives [source: Lugar].
But modern societies have become much more efficient -- and deadly -- at fomenting hatred, as we'll discuss on the next page.