Descartes argues that the mind and the body must be two different things since he knows the mind exists but knows no such thing about the body. Spell out this argument. What's wrong with it, if anything? Give a counterexample to the principle implied here.
Are other philosophers that we have read drawing conclusions about what the mind must be like based on what we know about the mind or how we know it? Is that always a mistake? Can reasoning like this be defended? Maybe even Descartes's reasoning?
Descartes on the dualism of mind and body
Descartes insists that mind and body are each distinct from the other although 'living together' in one 'package. His reasoning for this includes the following:
Mind and body are two different organisms. You see this clearly from the way they are fashioned. Each looks and behaves so different to the other, therefore how can they be one? Each, consequently, exists separately from the other and is dependent one from the other.
We describe mind and body in different ways. Descartes in his "Meditations," describes humans as 'thinking beings'. Humans are thinking thing or mind but they are so due to the MIND. The body is essentially flesh that is corporeal; it lacks senate ability. It therefore cannot react in the same way stone, bone or other inanimate thing lacks capability of reaction. Material things, such as the body, are measured and defined in terms of size, weight, and so forth. The brain/mind, on the other hand, is innominate. It is the receptacle of thought and thought cannot be measured in ways that physical aspects are. Hence, body and mind are two separate factors.
3. Death is the conclusive factor that mind and body are distinct. In this life, they seem to act together. Each feels the same pain. Once death comes, soul / mind are separated form body. We see body then as it is: flesh. In other words, it is death that shows that mind and body are two distinct elements.
Descartes argued that it is true that we tend to ascribe anthropomorphisms to the body (e.g., I see; I think etc.) instead of delegating those to the mind, but then people have always ascribed knowledge to inanimate things like stones, plants, or animals. Descartes gave the example of gravity where it was said that stones fall downwards because they are trying to reach their goals of hitting earth (AT VII 442: CSM II 298). In the same way, people ascribe humanist terms to the body.
Philosophers who agreed with Descartes
Plato was one classical philosopher who supported Descartes's dualism. He, for instance, sees death as a good thing since, in death, body, that distracts mind, is separated from mind and mind is finally able to merge itself with the Ideals, or the absolute good. Access to these Ideals affords us true bliss and Knowledge (which is the essence of intimate contact with a God, or the immoveable being of all who stands outside the world). However, since we are in this corporeal world, we are distracted by our body and by physicality from these Real substances. The philosopher, therefore, looks forward to death when his soul will be separated from the distracting body and be able to clearly and keenly perceive the Forms in their undiluted essence.
Aristotle shared Plato's views on dualism and, in line with Plato, supported the position of multiple souls. To him, soul had different characteristics according to the level of entity in the hierarchy with people -- uppermost in the hierarchy -- possessing the most complex soul. Plato, however, separated soul form body at death, whereas Aristotle saw soul perishing with body when body expired.
Later traditions, such as Neo-Platonism and scholasticism, made famous under the teaching of St. Thomas Aquinas and immortalized under Catholicism, elaborated on the dualistic tradition.
Philosophers who oppose Descartes
Philosophers who opposed Descartes' vision of separateness of mind and body generally pace their arguments on physicalism, namely on reduction of mind to physical factors, otherwise called monism (of one total whole). The most common monism are all variations of physicalism in some form or other; these positions include behaviorism, the type identity theory, anomalous monism and functionalism (Kim, 1995).Both Parmenids and Spinoza are two early philosophers who articulated this perspective.
Searle was a more recent thinker who built his refutation on neuroscience: "Mental phenomena are caused by neurophysiological processes in the brain and are themselves features of the brain.". The whole, in other words, is reducible to physical components. Searle exemplifies this with the liquidity-H20 relationship. The liquidity of the water is only due to the molecular components of the water. You cannot say that they are two different components. The molecular elements cause the liquidity. Similarly (Searle argued) one cannot divide the world into mental and physical constructs. Everything is physical; there simply happens to be mental physical things and non-mental physical things.
He showed that mind and body are intimately linked arguing that when, for instance, I want to raise my hand (i.e., when mind tells body to raise limb) my hand shoots up. In a similar way, when the body hurts, it is the mind telling it so. The two are so tightly conjoined; it forces me to say: "I feel hurt." There is no difference. I t is holistic. The two, in other words, are so intimately conjoined that no difference can be made between body and mind. Rather, mind, as Gilbert Ryle would say, is the 'Ghost in the Machine' (namely that it is an error in terms of construct: we think an additional component to be there when, in the end, all is reducible to one single entity).
Descartes foresaw this argument and refuted it. He responded that we may explain this with cause and effect. Namely, the mind -- independent as it is -- intends to do a certain action, and effect follows in that body obeys. We may see the two, so instinctive and indiscernible in gap one form the other, as being collapsed in the one action (Mind/body) but, nonetheless, there is an indiscernible momentary gap between commands of the brain and obedience of the body. This momentary gap indicates separateness of the two entities.
Searle's other criticism may have been harder for Descartes to handle. Searle argued that, according to Descartes's principles of Mechanics, mind has to be physical for it to have an effect. Likewise, it has to have a surface to act. Yet, Descartes stated uniqueness of mind and uniqueness of body with each having its specific characteristics. Mind has its metaphysical concepts whilst body has its physical components. How, Searle argued, can mind act without surface power. Descartes's entendre was inconclusive. Scholars read him as saying that it is a false presupposition that two substances with completely different natures cannot act on each other. They can in ways that may yet be concealed to us. Both mind and body are finite elements and, therefore, they may have an impact on one another in ways that we do not understand. This appeal to ad ignoratum is unsatisfactory.
Ultimately, the argument of monists such as Searle, Spinoza, and numerous others, are supported by the irrefutable evidence of natural science, in particular neuroscience which shows mind to be reducible to materialist factors.
Arguments against physicalism
The most popular argument that is brought against monism / phsycialism is that of the challenge of combining qualia (i.e. consciousness) with physicality. The two, as Descartes, pointed out, re utterly distinct. How can the existence of qualia exist in an utterly physical world? Hempel's dilemma sharpens this quandary by pointing out that physicalism may not be inappropriately defined, nor do we know what a future possible physical theory may postulate (Melnyk, 1997).