Argumentum

Argumentum is a Latin term that translates roughly as "proof" or "argument." In scholarly usage it denotes a line of reasoning offered in support of a claim. The word derives from arguere, meaning "to make clear, prove." In classical rhetoric and scholastic logic, an argumentum comprises the premises and the inferential step that leads to a conclusion; it can be deductive (where the conclusion follows necessarily from the premises) or inductive (where the conclusion is supported to varying degrees by the premises). In rhetoric, argumentum refers to the logical core of an appeal, i.e., the logos component, as opposed to ethos (character) and pathos (emotions).

Different sources of argumentum include formal demonstrations (syllogisms), causal inferences, analogies, and testimony or authorities. In medieval and early modern texts, scholars discuss various argumenta as methods of proving or persuading. In contemporary English usage, the word is largely replaced by "argument" or "proof," and the term argumentum is most often encountered in historical discussions or as part of Latin phrases such as argumentum ad hominem or argumentum ad populum, which describe specific types of argumentation (often as fallacies) rather than sound proofs.

See also: argument, syllogism, reductio ad absurdum, ad hominem, ad populum.