In the 17th century, the rationalist philosopher and mathematician René Descartes formulated the philosophy of dualism to address questions regarding the existence of the mind and its relation to the physical universe. In basic terms, he said that the human being is made up of extended substance and thinking substance. The former consists of flesh, bones, and other forms of matter featuring physical dimensions such as length, width, and height. The latter on the other hand, comprises the mind, which has no physical manifestation. Descartes further asserted that events occurring in the mind correlate with events occurring in the extended substance of a human being. Although this philosophy has great common sense appeal, it can be effectively doubted.
Imagine someone snapping his finger. Where did this action originate? Trace it. Surely a nerve impulse was sent from the brain to the finger, but where did that impulse originate? Most would say the mind, but the mind has no physical manifestation.
Now look at nature. What is the origin of universal gravitation? Trace it. Just as in the former case, we do not perceive the origin for certain, but unlike the former case, we hypothesize the origin not as a mind, but as an imperceptible, intrinsic, mechanical system. Why the contradiction? Perhaps as in the case of the snapping of a finger, there is a mind without physical manifestation behind universal gravitation and other natural phenomena. Alternatively, perhaps as the origin of action in nature consists just of matter and energy revolving around time according to laws spontaneously and intrinsically born, perhaps the origin of human action is also pure mechanics rather than the will of the mind. This would mean that the distinctions of the universe set up by Descartes in the 17th century are false, and that either both nature and man possess a thinking substance, or everything is only extended substance.
What do you think?