As the ego cogito, subjectivity is the consciousness that represents something, relates this representation back to itself, and so gathers with itself.
- Martin HeideggerCogito cogito ergo cogito sum (I think that I think, therefore I think that I am.)
- Ambrose BierceCogito ergo sum. (I think; therefore I am.)
- Adnan DulaimiDubito ergo cogito; cogito ergo sum.
- Rene Descartes