I Think, Therefore I Am in Latin: __ergo Sum
Puzzle 20 of City Nicknames Hard Pack
Question is: I Think, Therefore I Am in Latin: __ergo Sum
and the answer is: COGITO
Word Meaning:
COGITO — (philosophy, often preceded by the, sometimes capitalized) The argument "cogito, ergo sum" ("I think therefore I am") from the philosophy of René Descartes; the mental act of thinking this thought; a conscious being which performs this mental act.
Definitions from Wiktionary.