Descartes’ statement, "Cogito ergo sum" commonly translated as “I think therefore I am,” was originally instigated by doubting everything ever known to him. He doubted the existence of broad topics such as the universe as well as narrower topics such as his own existence. The mere fact that he doubts such aspects of human life supports the idea that he thinks and in turn exists. Similarly, his life is validated due to his doubts about his existence. The fact that he is able to rationalize these thoughts about his existence indicates that his presence in reality is true.
After we discussed this subject in class, I wondered how Descartes would interpret the case of a coma patient. A coma patient with severe brain damage is unable to respond to pain, light, or any external factors. If a coma patient is having irregular heartbeats or difficulty breathing, then he is put on a respirator so that blood and oxygen can reach the brain. The respirator is used to keep the involuntary functions of the brain working. As a result, the brain keeps operating to help the body stay “alive.” Without the respirator, the patient would not be living for much longer since his brain would not be functioning. A coma patient is unconscious to all of reality and cannot be awoken from this vegetated state. Unconsciousness hinders the ability to recognize the external and as a result the ability to doubt the external is affected; therefore unconsciousness affects the patient’s ability to think at a conscious level. For Descartes, a coma patient might be considered nonexistent on the basis that he is not able to consciously think on a level of consciousness; therefore, because he is not thinking, he cannot exist. However, according to the practice of medicine, a patient in a coma is alive as long as his brain is still helping his heart and lungs function. The respirator keeps the brain working hence medically the patient is still living. Both of these views contradict each other in the debate regarding whether or not the coma patient exists.
So I wonder, is this coma patient alive because his brain is in fact working though it is assisted by a respirator or , would he be considered nonexistent because he is unable to think therefore does not fulfill Descartes‘ definition of existence?
Lastly, is there any possible way to prove that the patient is thinking at a subconscious level and is in fact capable of thoughts and possibly doubting a new reality even while unconscious?