People filled with hate sometimes do incomprehensible things, from defacing gravestones to stalking and killing people. But is their extreme animosity a form of mental illness?
In 1999, Eric Harris and Dylan Klebold attacked their high school in Columbine, Colo., killing 12 students and a teacher and wounding 24 others, and left behind hateful online rants against society to explain their actions [source: Chua-Eoan]. But it also soon emerged that Harris had been treated with medication for depression, and some believed his despair made him more susceptible to hatred [source: Associated Press]. Other even more notorious hate-mongers, like Hitler and Osama bin Laden, have been diagnosed by mental health experts -- albeit from a safe distance -- as suffering from narcissistic personality disorder and other mental conditions [sources: Coolidge, Diamond].
Based on those examples, it's tempting to jump to the conclusion that those who feel hatred toward others are mentally ill. But that doesn't explain the vast numbers of ordinary Germans and Bosnian Serbs who morphed from friendly neighbors to eager murderers of their countrymen. That's why some mental health experts think that if the tendency to hate is a disease, it's more akin to herpes than a rare cancer.
Early 20th century psychoanalytic pioneer Sigmund Freud, for example, regarded hate as a normal, albeit unpleasant, byproduct of an individual's struggle to maintain and preserve his or her ego in the face of civilization's pressures [source: Abel]. Others think that even ordinary, well-socialized people can be induced to hate others, if they're subjected to sufficient trauma. A 2000 study of adults from war-torn Kosovo, for example, found that those who had suffered the most psychological stress and illness also tended to harbor the most extreme feelings of hatred toward the Serbian troops who had been their tormentors [source: Healy].
But others say that, like a loaded gun, hatred isn't inherently bad -- that it's merely a capacity that can be used for good as well as evil. Psychiatrist and writer Kurt R. Eissler, for example, defended "noble hatred," in which an intense aversion is put to a constructive use, such as overthrowing a cruel dictator. "The activation of compassion would only diminish the impetus of his attack against superior power," he wrote. For a revolutionary fighting against injustice, Eissler argued that hatred is not only normal, but actually can be a positive tool for all of us [source: Bartlett].