War has reliably ravaged humanity in every era and in virtually e':'ery society. Some say it will always be with'us, for the propensity for violence is an indelible human trait, as if mass killing was somehow etched into human genes. Others are more optimistic, convinced that someday humans will overcome their aggressive urges and eradicate war from the planet. Whatever the case, perhaps we can draw some encouragement from the fact that the ethics of war-the philosophical study of the morality of warfare--continues to shed light
on the subject, yielding more understanding than most people would think possible.
Like war, the study of the right and wrong ofwar has ancient roots, dating back to great thinkers such as Aristotle (384-322 B.C.E.), Cicero (106-43B.C.E.), Augustine (354-430 c.E.), Averroes (1126-1198), Thomas Aquinas (1225-1274), and Hugo Grotius (1583-1645). In fact, their insights on the;subject still constitute the core of the best think.lng today.