section_path: Physics/Philosophy, metaphysics, and physics
section_name: Philosophy, metaphysics, and physics
paragraph_text: Philosophy, metaphysics, and physics
  
  Descartes is often regarded as the first thinker to emphasize the use of reason to develop the natural sciences. For him, philosophy was a thinking system that embodied all knowledge, as he related in a letter to a French translator:
  
  Thus, all Philosophy is like a tree, of which Metaphysics is the root, Physics the trunk, and all the other sciences the branches that grow out of this trunk, which are reduced to three principals, namely, Medicine, Mechanics, and Ethics. By the science of Morals, I understand the highest and most perfect which, presupposing an entire knowledge of the other sciences, is the last degree of wisdom.