The phrase ad hominem is short for argumentum ad hominem or “argument to the man.” This the classic personal attack in which someone seeks to win a debate by personally abusing his opponent rather than by engaging the issue at hand. It is very common in political debate and controversy.
The word hominem is derived from the Latin homo, homenis, which means “man.” It is related to the Latin word humus (“earth”) and humanus (that one “of the earth,” the human). You will also recognize homo in the phrase homo sapiens—the “wise” man.
The Latin word humanitas described the state of a cultivated or educated human with well-developed human capacities. From humanitas we derive our ideas of the “humanities”—those arts that perfect our human capacities to use language and mathematics, for example.