cogito
noun
co·gi·to ˈkä-gi-ˌtō 
ˈkō- ˈkä-ji-
ˈkō- ˈkä-ji- 1
: the philosophical principle that one's existence is demonstrated by the fact that one thinks
2
: the intellectual processes of the self or ego
Example Sentences
Recent Examples on the Web Played by Sandler as the cogito-ergo-sum of his ambitions, Howie is in many ways the human embodiment of that Furby, a soul held hopelessly in place by the transactional madness of his reality. 
Isaac Feldberg, Fortune, 23 Dec. 2019
Isaac Feldberg, Fortune, 23 Dec. 2019 Word History
Etymology
New Latin cogito, ergo sum, literally, I think, therefore I am, principle stated by René Descartes
First Known Use
1838, in the meaning defined at sense 1