Final answer:
Yes, René Descartes had peers who believed in his theories, particularly his influential concept of mind-body dualism. His philosophical frameworks sparked significant discussions and influenced various fields, showing that he had a following that supported and built upon his ideas.
Step-by-step explanation:
Did René Descartes have peers who believed in his theories? The answer is A. Yes. Descartes' innovative ideas in philosophy, especially mind-body dualism, sparked significant philosophical discussions during his time. He proposed a profound skepticism and a radical method of doubt to reach undeniable truth which eventually culminated in his famous conclusion 'Cogito, ergo sum.' (I think, therefore I am). This assertion served as a foundational element in his philosophical framework which influenced succeeding schools of thought. Descartes' works also paved the way for modern epistemology, contributing to advancements in various fields including politics and science. Although his proof concerning the existence of the soul separately from the body was subject to serious criticism, some contemporaries and later philosophers, particularly those involved in the Cartesian tradition, did support and build upon his ideas.
Furthermore, Descartes' theories on animals' lack of reasoning abilities influenced some of his followers to believe that animals did not have mental states, such as pain. This also indicates that he had a following that adhered to his views. The scope of his influence indicates that while not universally accepted, Descartes indeed had peers who believed in his theories.