“Therefore. Ergo. Erg. Argh. Ugh.”
“Dubito, ergo cogito, ergo sum.(English: "I doubt, therefore I think, therefore I am")”
“Cogito ergo sum. (I think, therefore I am.)”
“I am not much for philosophy, but that old Descartes, he got me thinking. And therefore being. Anyone? Anyone? Cogito ergo sum jokes? No? Okay.”
“Cogito ergo sum, certamen ergo sum.”
“Cogito cogito ergo cogito sum -- "I think that I think, therefore I think that I am;" as close an approach to certainty as any philosopher has yet made.”