In Decartes’ “Meditations” he is famously known for casting a great doubt upon himself in order to examine his beliefs. This is in order to rebuild his world view based solely on clear and distinct ideas. There are many snippets in Descartes’ “Meditations” but his crown jewel is primarily the cogito. The cogito has been a topic of debate a lot as of recent, especially by those with an interest in undermining previous philosophical authorities like Descartes. It is similar to attacking an enemy, having the most vital asset of theirs as the main objective in hopes that the less important ones will die off without support. It is important to note we as philosophers always give the principle of charity to others expressing their philosophy, even if it is opposite to ours. It’s especially necessary to give charity to someone who has been dead for nearly 400 years. When this is the case it is best to give the philosopher the benefit of the doubt.
To make this story short, Descartes gets to a point in his doubt that he is unsure of anything as it is possible in nearly every way for him to be deceived either by himself or some sort of demon. It is his logic at this point in his doubt that he comes to his first truth beyond doubt. That he exists. Cogito ergo sum, most often translated “I think, therefore I am”, is typically how this realization is portrayed to students and anyone with a basic interest in historical philosophy. This can be interpreted as existence being the result of thinking which is I feel misrepresented as being what Descartes’ meant. Imperative to the logic he used previously to support this statement is his acknowledgement that it could be possible everything that he thinks is false. However, even if he is deluded he must exist in order to be deluded. As well as even if the devil himself were to make it so that he no longer exists, he cannot make it so that Descartes never existed at all because he knows in the moment that he does.
So it is not that he exists, because he thinks. Which is what is often said about his conclusion. It has been argued that he should have said it in reverse such as ‘I am, therefore I think’ in an attempt to correct Descartes. By the logic he himself uses though, it is clear he exists simply because he is aware of thoughts. Not because he is thinking. If Descartes were to ever know he was not thinking, he would arrive at the same conclusion.