Cogito, ergo sum

Cogito, ergo sum, “I think, therefore I am.” Descartes' principle of certainty, and on which, as on a stable basis, he reared his whole philosophy. See Descartes. “Alas, poor cogitator,” Carlyle exclaims, “this takes us but a little way. Sure enough, I am; and lately was not; but Whence? How? Whereto?”

Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)

Cœur de Lion * Cognac
Codrington, Sir Edward
Codrington, Sir William John
Codrus
Coehoorn, Baron van
Cœlebs
Cœle-Syria
Cœlian
Coello
Cœur, Jacques
Cœur de Lion
Cogito, ergo sum
Cognac
Cogniet
Coila
Coimbatore
Coimbra
Coke
Coke, Sir Edward
Colbert, Jean Baptiste
Colburn, Zerah
Colchester