 A demonstration is a syllogism that brings about knowledge (NLP I.5, 31). A syllogism is “an expression in which a conclusion follows of necessity when certain things have been asserted” (DOS 493, Kretzmann 1988, 265). The material principles of the syllogism are the three terms (remote matter)—the two extremes (major, minor) and the middle—combined into two premises (proximate matter). The conclusion is not part of the syllogism.