Final answer:
Descartes's strategy of doubt consists of hypothesizing about an evil demon that could deceive us about the external world and establishing his own existence through the undoubtable act of thinking, leading to Cartesian Dualism.
Step-by-step explanation:
Two elements of Descartes's strategy of doubt are the use of skeptical hypotheses, such as the possibility of an evil demon deceiving us, and his establishment of a foundation for certain knowledge through the cogito, expressed as 'Cogito, ergo sum' (I think, therefore I am). Descartes's meditations involved systematic doubt to question the reliability of our senses and the existence of the external world. By entertaining the notion of an evil demon with the power to manipulate our perceptions, he proposes a scenario where external reality could be entirely false. However, despite this powerful skepticism, he identifies the act of thinking as undeniable and self-evident, thus establishing the certainty of one's own existence as a thinking entity. The fundamental principle that one can be certain of their existence through the act of thinking sets the stage for the development of his dualist philosophy, distinguishing between the mental and physical realms (Cartesian Dualism).