Was René Descartes a philosopher or a scientist?

Rene Descartes is most widely regarded as a philosopher. One of his most famous quotes is "I think; therefore, I am" (in the original French: "Je pense, donc je suis.") However, Descartes was also a scientist, who carried through multitudes of experiments. For instance, it was Descartes who dissected animals and developed the theory that animal spirits were carried through hollow tubes (now known as nerves) to allow movement. Thus, the answer to your question: Rene Descartes, though known primarily as a philosopher, was both a philosopher and a scientist.