We may conclude that Descartes was aware of the temptation to present mind and body as competing and cooperating substances and he tried to escape the dualism, not only because any dualism is in need of some mediation, as the involvement of animal spirits proves, but also and foremost because of its explanatory deficits.
On the one hand, his view appears to embrace the dualism that comes with inherited language for instance from Platonism and Aristotelianism.
On the other hand, if the philosophical problem of mind is that of understanding human knowledge, then understanding must be accessible to material beings and not within the realm of the immaterial. Therefore, Ryle was right to believe that Descartes fundamentally missed the task of understanding the mind. To summarize the main points of the role of Descartes at the origin of modern philosophy of mind and specifically of substance dualism: Descartes aimed initially at proving that the human soul is immaterial as Christian doctrine teaches ; for that purpose he emphasized the certainty of rational thinking and its independence from body and material objects.
This led him to the still debated question of how the mind can work with the body in the process of sense perceptions, feelings, etc. As a consequence, he explained great deal of intellectual functions perceptions, emotions, etc. At the same time he underlined the immateriality of thinking.
In traditional philosophical terminology, this amounted to the theory of two totally distinct substances: mind and body. However, it should be noted that Descartes undermined the concept of substance and reduced it to something deliberately vague. Therefore, philosophers who cling to the notion of substance as a reality will find substance dualism in Descartes; others, who focus on his attempts at explaining mental operations like perceptions and feelings in corporeal terms, will find him to be a proponent of physicalism.
Adam, Charles and Paul Tannery, eds. Oeuvres de Descartes. Paris: Vrin. Campanella, Tommaso. Compendio di filosofia della natura , eds.
Germana Ernst and Paolo Ponzio, sect. Santarcangelo di Romagna: Rusconi. Cottingham, John G. The Philosophical Writings of Descartes , 3 vols. Cambridge: Cambridge University Press. Ryle, Gilbert. The Concept of Mind. Sepper, Denis L. Lawrence Nolan, New York: Cambridge University Press. Ariew, Roger. Descartes among the Scholastics. Cottingham, John. John Cottingham, Hassing, Richard F.
Lanham: Lexington Books. Markie, Peter. Ruler, Han van. North , eds. Lodi Nauta and Arjo Vanderjagt, Leiden: Brill. Truly, when Descartes argues in favor of dualism between the extended and the non-corporeal substances, he is completely radical about their separation.
So, when he asserts the union between the human mind and body, some interpreters find that he presents a contradictory position. Others think that probably Descartes was not so radical in his dualism.
In order to build a different interpretation about the Cartesian dualism and the union of mind and body, I have established two categories. I call diachronic interpretations those that maintain that Descartes was first a dualist i.
Against diachronic perspectives, I propose a synchronic interpretation under which I maintain that Cartesian dualism and the union of mind and body are simultaneously present all along Descartes works. In his letter [] Descartes justifies this saying he had been primarily focused in the demonstration of the distinction between mind and body. Descartes himself recognized the uneven development of his doctrine on dualism and his doctrine on the union and interaction of mind and body. I think that, as a consequence of this unequal treatment of dualism and union, from Descartes days until now, there has been a large tendency to understand them as conceptions that developed successively.
Gassendi and Elisabeth had diachronic interpretations, and nowadays many authors maintain similar views on Descartes doctrines on union and dualism. I do not have enough space to discuss here any particular diachronic interpretation.
Besides, it is widely accepted that the distinction between extended and non-extended substances was previously conceived by Descartes, and that it is the departing point to explain the union of mind and body and its interaction. In effect, Cartesian dualism claims the independent existence of a non-corporeal realm and a physical realm. But, at the same time, through his works, whenever Descartes presents the distinction between thought and matter, he mentions the tight relation in the human beings between mind and body.
In the Sixth Meditation, we can see that Descartes comes to the conclusion that my essence consists solely in the fact that I am a thinking thing, and immediately after affirms that he certainly has a body that is very closely joined to me [AT IX 62; CSM II 54]. In this passage the union is initially mentioned as a possibility, but right away, to anticipate says Descartes, it is stated with certainty.
Here, Descartes tells us about the fact of the union, but he does not give any further explanations. Anyway, these are not necessary, because what follows in his argument is that, despite this union, there is no obstacle to affirm that I have a clear and distinct idea of myself, in so far as I am simply a thinking, non-extended thing; and on the other hand I have a distinct idea of body, in so far as this is simply an extended, non-thinking thing. Dualism and union are present in the same argument, but while the former is the main topic and Descartes center of attention, the latter is only mentioned as a fact.
Now, the first step of my synchronic interpretation is to point out the simultaneous presence of dualism and union. But, of course this does not save Descartes from the accusation of having an incoherent conception about the substantial distinction and the union and interaction of mind and body. On the one hand, we know that one of the main roles of Cartesian dualism is to found metaphysically his physical science, and for this reason Descartes gave especial attention to dualism. On the other hand, it was not until his final works that he found necessary to say more about the union and interaction of mind and body.
Anyway, what must be quite clear is that whenever Descartes argued in favor of the substantial distinction, he also mentioned the particular case of the union of mind and body in the human beings. So, instead of insisting in the possible contradictions between dualism and union, I prefer to follow a new direction and try to find the place of each of these doctrines in the Cartesian system.
In a famous passage in the Sixth Meditation, Descartes denies that the mind is merely present in the body. For him, the mind is very closely joined and intermingled with the body. It existed before it acquires a body. A third argument from the Phaedo is the Argument from Affinity.
Socrates claims that things that are composite are more liable to be destroyed than things that are simple. The Forms are true unities and therefore least likely ever to be annihilated.
Socrates then posits that invisible things such as Forms are not apt to be disintegrated, whereas visible things, which all consist of parts, are susceptible to decay and corruption. Since the body is visible and composite, it is subject to decomposition. The soul, on the other hand, is invisible.
The soul also becomes like the Forms if it is steadfastly devoted to their consideration and purifies itself by having no more association with the body than necessary. Since the invisible things are the durable things, the soul, being invisible, must outlast the body. Further, the philosophical soul, that becomes Form-like, is immortal and survives the death of the body.
Traces of the Affinity argument in a more refined form will be observed in Descartes below. The Argument from Opposites applies only to things that have an opposite and, as Aristotle notes, substances have no contraries.
Further, even if life comes from what is itself not alive, it does not follow that the living human comes from the union of a dead i.
The principle that everything comes to be from its opposite via a two-directional process cannot hold up to critical scrutiny.
Although one becomes older from having been younger, there is no corresponding reverse process leading the older to become younger. If aging is a uni-directional process, perhaps dying is as well. Cats and dogs come to be from cats and dogs, not from the opposites of these if they have opposites. The Arguments from Recollection and Affinity, on the other hand, presuppose the existence of Forms and are therefore no more secure than the Forms themselves as Socrates notes in the Phaedo at 76d-e.
In the Sixth Meditation, Descartes calls the mind a thing that thinks and not an extended thing. He defines the body as an extended thing and not a thing that thinks , p. A thing that thinks. What is that? A thing that doubts, understands, affirms, denies, wills, refuses, and which also imagines and senses. Bodies, but not minds, are describable by predicates denoting entirely quantifiable qualities and hence bodies are fit objects for scientific study.
I seem to find evidence that the part of the body in which the soul exercises its functions immediately is. Conversely, the body is also able to influence the soul.
It is clear, then, that Descartes held to a form of interactionism, believing that mental events can sometimes cause bodily events and that bodily events can sometimes cause mental events. This reading of Descartes-as-interactionist has recently been challenged. See Baker and Morris Also, Daniel Garber suggests that Descartes is a quasi-occasionalist, permitting minds to act on bodies, but invoking God to explain the actions of inanimate bodies on each other and phenomena where bodies act on minds, such as sensation.
See Garber, , ch. Although the whole mind seems to be united to the whole body, nevertheless, were a foot or an arm or any other bodily part amputated, I know that nothing would be taken away from the mind. Decartes argues that the mind is indivisible because it lacks extension. The body, as an object that takes up space, can always be divided at least conceptually , whereas the mind is simple and non-spatial.
More formally, x is identical to y if, and only if, for any property p had by x at time t, y also has p at t, and vice versa. Although it makes sense to speak of the left or right half of the brain, it makes no sense to speak of half of a desire, several pieces of a headache, part of joy, or two-thirds of a belief. What is true of mental states is held to be true of the mind that has the states as well. The mind has many ideas, but they are all ideas of one indivisible mind. John Locke argued that awareness is rendered discontinuous by intervals of sleep, anesthesia, or unconsciousness.
II, ch. I, sect. Is awareness then divisible? Locke suggests that the mind cannot exhibit temporal discontinuity and also have thought as its essence. But even if Descartes was wrong to consider the mind an essentially thinking thing, the concept of mind is not reduced to vacuity if some other, positive characteristic can be found by which to define it. But what might that be? Without some such means of characterizing the mind it would be defined entirely negatively and we would have no idea what it is.
Against Locke, Dualists can argue in several ways. Locke argues that such a maneuver creates grave difficulties for personal identity Bk. II, Ch. The Argument from Indivisibility seeks to show that bodies but not minds are spatially divisible and that argument is not rebutted by pointing out that consciousness is temporally divisible.
Indeed, if minds are temporally divisible and bodies are not, we have an argument for dualism of a different sort. David Hume , on the other hand, questioned of what the unity of consciousness might consist. The Indivisibility Argument suggests that the mind is a simple unity. Hume finds no reason to grant or assume that the diversity of our experiences whether visual perception, pain or active thinking and mathematical apprehension constitute a unity rather than a diversity. For Hume, all introspection reveals is the presence of various impressions and ideas, but does not reveal a subject in which those ideas inhere.
Accordingly, if observation is to yield knowledge of the self, the self can consist in nothing but a bundle of perceptions. However, Kant agreed that we must not mistake the unity of apperception for the perception of unity—that is, the perception of a unitary thing or substance. Kant also argued that there is little reason to suppose that the mind or ego cannot be destroyed despite its unity since its powers may gradually attenuate to the point where they simply fade away.
The mind need not be separated into non-physical granules to be destroyed since it can suffer a kind of death through loss of its powers. Awareness, perception, memory and the like admit of degrees. If the degree of consciousness decreases to zero, then the mind is effectively annihilated. Even if, as Plato and Descartes agree, the mind is not divisible, it does not follow that it survives or could survive separation from the body. Additionally, if the mind is neither physical nor identical to its inessential characteristics , p.
Kant argues that two substances that are otherwise identical can be differentiated only by their spatial locations. If minds are not differentiated by their contents and have no spatial positions to distinguish them, there remains no basis for individuating their identities.
On numerically individuating non-physical substances, see Armstrong, , pp. For a general discussion of whether the self is a substance, see Shoemaker, , ch. After taking up his celebrated method of doubt, which commits him to reject as false anything that is in the slightest degree uncertain, Descartes finds that the entirety of the physical world is uncertain.
Perhaps, after all, it is nothing but an elaborate phantasm wrought by an all-powerful and infinitely clever, but deceitful, demon. Still, he cannot doubt his own existence, since he must exist to doubt. Because he thinks, he is. But he cannot be his body, since that identity is doubtful and possibly altogether false.
In sum, I cannot doubt the existence of my mind, but I can doubt the existence of my body. From this I knew that I was a substance the whole essence or nature of which was merely to think, and which, in order to exist, needed no place and depended on no material things. The Argument from Indubitability has been maligned in the philosophical literature from the very beginning. Perhaps it also belongs to my essence to be something extended. Suppose that I cannot doubt whether a given figure is a triangle, but can doubt whether its interior angles add up to two right angles.
It does not follow from this that the number of degrees in triangles may be more or less than This is because the doubt concerning the number of degrees in a triangle is a property of me, not of triangles.
The dualist can reply in two ways. First, he or she may argue that, while doubting the body is not a property of bodies, being doubtable is a property of bodies. Second, the dualist may reply that it is always possible to doubt whether the figure before me is a triangle.
Consider, for example, the following parallel argument from Paul Churchland , p. Following Descartes, it ought to be that Ali is not Clay though in fact Clay was a famous heavyweight and identical to Ali. By way of reply, surely it is possible for an evil demon to deceive me about whether Mohammed Ali was a famous heavyweight boxer.
So, the dualist might insist, the case of mind is unique in its immunity from doubt. It is only with reference to our own mental states that we can be said to know incorrigibly. A third argument in the Meditations maintains that the mind and body must really be separate because Descartes can conceive of the one without the other. Since he can clearly and distinctly understand the body without the mind and vice versa, God could really have created them separately.
But if the mind and body can exist independently, they must really be independent, for nothing can constitute a part of the essence of a thing that can be absent without the thing itself ceasing to be. If the essence of the mind is incorporeal, so must be the mind itself. The general strategy is to identify some property or feature indisputably had by mental phenomena but not attributable in any meaningful way to bodily or nervous phenomena, or vice versa.
For example, some have suggested that mental states are private in the sense that only those who possess them can know them directly. The latter assumes a correlation, if not an identity, between nervous and mental states or events. My linguistic, bodily and neural activities are public in the sense that anyone suitably placed can observe them. Since mental states are private to their possessors, but brain states are not, mental states cannot be identical to brain states.
Rey pp. Others can know my mental states only by making inferences based on my verbal, non-verbal or neurophysiological activity. You may infer that I believe it will rain from the fact that I am carrying an umbrella, but I do not infer that I believe it will rain from noticing that I am carrying an umbrella. I do not need to infer my mental states because I know them immediately.
Since mental states are knowable without inference in the first person case, but are knowable or at least plausibly assigned only by inference in the third person case, we have an authority or incorrigibility with reference to our own mental states that no one else could have. Since beliefs about the physical world are always subject to revision our inferences or theories could be mistaken , mental states are not physical states.
Some mental states exhibit intentionality. Intentional mental states include, but are not limited to, intendings , such as plans to buy milk at the store.
They are states that are about, of, for, or towards things other than themselves. What then of mental state 1? The identity theorist says that mental state 1 must then have been included in physical state 1.
What does the dualist say of mental state 1? Gertler essentially arrives at the third. This is a much higher bar than just what scientists have arrived at in the study of structure and dynamics. Therefore, the physicalists require the same amount of armchair reasoning to defend their theses as dualists do theirs. The debate really comes down to what a person finds conceivable, she says. Dualists require conceptions of subjective consciousness and seemingly zombies.
Physicalists require conceptions of the structural-dynamic as being able to exhaustively explain all physical phenomena, which has not yet been proven. Functionalism also handles mental causation nicely as it is literally defines mental states causally the effects of certain causes and the causes of certain effects.
What about the thought experiments that prove dualism to be true, though? What about Mary and the zombie? Ann grows up in the normal world with normal colors, but she is just incapable of seeing red due to her not possessing the right cones.
She finds an eye surgeon who is capable and has the transplant performed on her. Walking outside the clinic, she sees a stop sign. She is seeing red for the first time. She has gotten a new skill, the ability to see red, but I do not see what she learns. She experiences all the physical effects of seeing red for the first time, but she has expected all of them. All of the workings of her brain are just as her scientific models have predicted because she knew everything.
The only thing that has changed is that she has gained the skill of seeing red and has now herself exhibited all the same physical effects of color vision that she had studied.
Cartesian dualism puts us in a place where we doubt the minds of others. All three of these are undesirable. Functionalism defines its mental states as existing in this causal chain, making mental causation easy while still avoiding the solipsistic potential conclusions of Descartes.
The main worry about functionalism and identity theory is it leaves out the key nature of the mental as qualitative and beyond the reaches of science. The thought experiments that one could propose to prove the qualitative nature of experience involve assuming existing agreement on dualism the zombie, who would be denied by identity theorists anyway or the mistake of thinking that acquiring a skill is learning a fact Mary, or even Ann. Thus, the functionalist view is the one I side with.
She is an incredible neuroscientist living in the distant future, in a time where literally everything physical about color vision is known.
In fact, she literally knows the wavelength of red.
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