principium

Principium is a Latin noun meaning beginning, origin, or source. In classical and medieval Latin it designated the starting point of a process, argument, or natural order. The term is the linguistic ancestor of English principle and related words in many Romance languages (Spanish principio, Italian principio, French principe).

Philosophical use: In philosophy the concept of a principium, or first principle (archē), is the foundational proposition or cause from which further reasoning proceeds. Aristotle discusses first principles as the bedrock of science; medieval thinkers sought principia to ground ethics, metaphysics, and natural philosophy. In modern thought the notion persists in debates over axioms, fundamentals, and the grounding of explanations. The Latin title Principia, as in Newton's Philosophiae Naturalis Principia Mathematica, uses principia in the plural sense “the principles” or “the starting points.”

Other contexts: In theology, principium can denote the origin of beings or the divine cause; in logic and epistemology, a principium is an axiom or premise. In linguistics or philology, principium sometimes refers to a root or origin of a term or concept, though this usage is less common.

Modern usage: Today the noun principium is primarily encountered in historical or formal discussions; in everyday usage, the English term “principle” and the phrase “first principle” are preferred. As a Latin term, principium remains a stylistic or scholarly reference, often appearing in translations of philosophical and theological texts.