1. the philosophical principle ‘I think, therefore I am’ formulated by René Descartes
Usage: philosophy

Examples

• Descartes’ cogito became the foundation of his philosophical system.
• The cogito represents the one thing that cannot be doubted.
• Philosophy students often begin by studying the cogito.
• The cogito ergo sum argument changed Western philosophy.
• She wrote her thesis on the significance of the cogito.