Dictionary
co•gi•to, er•go sum
Pronunciation: (kō'gi-tō" er'gō soom'; Eng. koj'i-tō" ûr'gō sum', er'gō), [key] Latin.
I think, therefore I am (stated by Descartes as the first principle in resolving universal doubt).
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.