Descartes and Dualism and Wittgenstein

This is interesting if you’d like to know whether body and mind are separate,as it were.

http://specterofreason.blogspot.com/2009/05/descartes-contra-wittgenstein.html

“Descartes’ famous principle, cogito ergo sum (“I think, therefore I am,” also known simply as the cogito), is probably the most widely known philosophical statement, and it is often considered to exemplify the only thing one can know for certain: that one exists.

The cogito might be considered an instance of modus ponens: “If I am thinking, then I exist; I am thinking, therefore I exist.” However, Jaako Hintikka (1962) compellingly argues that Descartes’ cogito ergo sum is not a logical inference at all, but a performative act: that a certain cognitive act instantiates direct knowledge of one’s existence–that the act of thinking makes one’s existence self-evident. On this view, “I think, therefore I am” is not a logical result, but expresses an inevitable consequence of thought itself. And because it is thought which manifests the necessity of the existence of the I, Descartes concludes that the I exists by virtue of thought alone. The I is, by definition, a thinking substance.”