Which philosopher is known for the idea of the evil demon causing doubt about existence?

René Descartes is the philosopher associated with the concept of the evil demon, which he introduced in his meditations on doubt and certainty. In his work, Descartes famously explores the idea that an all-powerful, deceptive being could manipulate our senses and perceptions, leading us to question the reality of the world around us. This thought experiment serves as a foundational element in his quest for indubitable knowledge, wherein he seeks to establish what can be known for certain despite potential deception.

Through this method of radical doubt, Descartes ultimately finds that while he can doubt the existence of the external world and even his own body, the very act of doubting confirms his existence as a thinking being, encapsulated in the phrase "Cogito, ergo sum" (I think, therefore I am). This pivotal realization marks a significant moment in philosophical thought, emphasizing the importance of skepticism in the pursuit of knowledge and the nature of existence.

The other philosophers listed have distinct contributions to philosophy, but they do not focus on the specific concept of an evil demon as a source of doubt in existence. Plato's idealism deals with the nature of forms and reality, Aristotle is known for his empirical approach to knowledge and categorization of the physical world