causa

Causa (rendered "KOW-sah," "legal case, cause, purpose") is one of the load-bearing nouns of the Latin record, and it turns up wherever Romans argue: 10,698 occurrences across 340 works. It gathers thickest in history and the courtroom. The heaviest count belongs to Ab urbe condita ("From the Founding of the City," 851), which the concordance attributes to Livy; then the Institutio Oratoria ("The Training of the Orator," 643), the Naturalis Historia ("Natural History," 419), the Epistulae ad Familiares ("Letters to Friends," 362), De Oratore ("On the Orator," 328), and In C. Verrem ("Against Verres," 322). This is a word at home where a reason is stated and a case is pleaded.

The lexica split on its first sense. De Vaan (Etymological Dictionary of Latin, Brill 2008) glosses it "legal case, trial; cause, purpose," marks it feminine, and dates it early — attested from the Lex XII (the Twelve Tables) and Naevius on, spelled caussa in inscriptions until the first century BC. He lists the family it grew: causari ("to plead a cause") and accusare ("to blame, charge"), with accusator ("prosecutor"). Lewis & Short (A Latin Dictionary, 1879) note the same older caussa in Cicero and record a guess — that the root may be cav- of caveo ("to be on guard"), the thing "defended or protected," compared with cura ("care"). That derivation they offer only as "perhaps."

For deeper ancestry the record holds pointers, not answers: two etymological treatments are matched — de Vaan (Brill 2008) and Ernout-Meillet (Dictionnaire etymologique de la langue latine, DELL, 1932; 4th ed. 1959) — but both appear as places to look, without a reconstructed root.

The citable surfaces are all Livy, book 1, the noun turning through its cases — causam, causa, causae — across the opening pages of Rome's story: the reason a thing was done, and the case for doing it.

If one word names both the cause of an act and the case argued for it, which came first in Roman ears — the reason, or the plea?