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Can Property Dualism Have Its Consciousness and Experience it Too? Part II

David Chalmers

David Chalmers

Philosopher David Chalmers argues that any version of physicalism cannot provide an adequate explanation of consciousness and how we have both mental states and physical states. In his essay Facing Up to the Problem of Consciousness, he distinguishes two different problems of consciousness as the easy problems and the hard problems (Chalmers 1995; 1-2). The easy problems are in explaining phenomena such as reportability of mental states, the focus of attention, the deliberate control of behavior and so on. He believes that this can all be explained scientifically and that the explanations for these can be reduced. We can explain the functionality of these phenomena (Chalmers 1995; 4). The hard problem on the other hand is a problem of how we come to have experience. The problems of consciousness that are considered hard problems cannot be adequately explained by scientific methods. For Chalmers, experience of the world is synonymous with qualia. He thinks that the hard problem is in how we explain how we have an experience of color or an experience of anything at all. Chalmers asks the question, “why should physical processing give rise to a rich inner life at all? It seems objectively unreasonable that it should, and yet it does” (Chalmers 1995; 3). The basic functions of the brain can be explained in reductive terms but the experiences cannot. Chalmers says there is an explanatory gap between the physical functions and conscious experience and we need an explanatory bridge in order to overcome this gap (Chalmers 1995; 6).


Chalmers proposes five strategies researchers in neuroscience and philosophers can take in approaching this explanation of consciousness. The first is to explain something other than the hard problems of consciousness. This strategy doesn’t really do much to forward our knowledge about how to come up with a bridge. It stays on the “easy” side of the gap (Chalmers 1995; 9). The second way is be an eliminativist about consciousness and deny its existence. Chalmers thinks that this is quite absurd and seems to be assuming a type of verification principle. He says that “a theory that denies the phenomenon ‘solves’ the problem by ducking the question” (Chalmers 1995; 9). A third option is for researchers to explain consciousness in the full sense, yet Chalmers thinks theories that which go for this option are nearly magical. This strategy doesn’t explain how consciousness emerges (Chalmers 1995; 9). A fourth approach seeks to explain the structure of experience. By explaining the visual structures in the brain one can explain how that relates to color. This strategy would still amount to staying on the “easy” side of the gap as opposed to actually building a bridge between the hard and easy problems (Chalmers 1995; 10). The last method is to “isolate the substrate of experience.” This method tries to “pick out” which process accounts for experience. This is still an inadequate strategy because we need to know why and how the process gives us consciousness. Chalmers parts ways philosophically with these five strategies because he thinks we need an “extra ingredient” to give us an adequate explanatory bridge (Chalmers 1995; 10). Given that all of the reductive explanations fail, we need a nonreductive explanation. He argues that “a nonreductive theory of experience will add new principles to the furniture of the basic laws of nature.” This theory adds properties as being fundamental (Chalmers 1995; 14). He admits that his position is a form of property dualism – what he calls naturalistic dualism.


Before we look at the arguments that Chalmers advocates for property dualism, we need to first make a few distinctions between different types of consciousness. When people talk about consciousness, invariably it seems like they’re talking about one thing. All the definitions of consciousness appear to be lumped together into one concept. Philosopher Ned Block thinks this is a misinformed notion and that there are different types of consciousness. Having a conceptual framework as to what consciousness is will help us tackle the problems of consciousness with more clarity and precision. Block’s first distinction of consciousness is phenomenal consciousness or what he likes to call P-consciousness. P-consciousness is the state of “what-is-it-like-ness” (Block 206). This type of consciousness is experiential. It is just one type of consciousness we have. This type of consciousness includes “properties of sensations, feelings and perceptions… thoughts, wants and emotions.” These properties are distinct from functional and cognitive properties of the brain (Block 206-7). Another type of consciousness is access consciousness or A-consciousness. “A representation is A-conscious if it is broadcast for free use in reasoning and for direct “rational” control of action (including reporting)” (Block 208). This A-consciousness is a direct awareness and form of reasoning in the mind, while P-consciousness is just states of experience or feelings.


This distinction can help us understand the easy and hard problems of consciousness with more clarity. The easy problems of consciousness are related to Block’s A-consciousness. They are forms of consciousness that we use to focus, control our behavior, and so on. This type of consciousness is still a form of consciousness. It isn’t any more or less important. The hard problem of consciousness would be problems of P-consciousness. Finding an explanatory bridge to the question “what is it like to be such and such” is a much harder question then seeing how the brain functions with forms of A-consciousness. It is with these conceptions in mind that we now will look at three arguments that Chalmers puts forth that will motivate people to a form of property dualism. It is careful to note that these arguments have type-type identity, and functionalism in its sights. They are arguments that seek to show the falsity of physicalist identity theories or notions of functional properties supervening on physical and mental states.


In his essay Consciousness and Its Place in Nature, David Chalmers considers two important arguments establishing that physicalism is false because it cannot explain the full scope of consciousness. The first argument is a conceivability argument. Chalmers asks us to imagine that there be a being that is physically identical to us. This being has all the same brain properties and brain states. If you scanned their brain everything would check out as being identical to our brain structure. These entities would even have access consciousness and would be able to be awake, report the contents of his internal states and so on (Chalmers 1996; 95). But, as it turns out, they lack any phenomenal conscious state. This entity is called a philosophical zombie. Unlike the zombies in movies and television, these zombies appear to be exactly the same as humans – in both behavior and on a neuronal level. They have absolutely no inner feel and do not have any experience of the world. If you were to ask them if they are conscious, they would tell you that they are. Chalmers states the argument as follows:

  1. It is conceivable that there be zombies.
  2. If it is conceivable that there be zombies, it is metaphysically possible that there be zombies.
  3. If it is metaphysically possible that there be zombies, then consciousness is non-physical.
  4. Conclusion: Consciousness is non-physical. (Chalmers 2003; 6)


These zombies are the same as us in regards to A-consciousness but are not the same as us in regards to P-consciousness, to reiterate Block’s distinctions. Chalmers is concerned with phenomenal zombies (Chalmers 1996; 95). Now it has to be said that much of this argument either succeeds or fails with premise (1). Conceivability is used to generate possibility. If I can conceive of X, then X must at least be possible. It is important to note that this phenomenal zombie might not in-fact be able to exist in the actual world. There might be physical limitations to this existing in our world. But, it does seem that these zombies can exist in at least some possible world, merely because they are conceivable. There doesn’t seem to be any contradiction in the idea of phenomenal zombies. It is a coherent idea. Chalmers argues that some burden of proof lies with the person who wants to argue that zombies are logically impossible (Chalmers 1996; 96). He gives a different example of the idea of a mile-high unicycle which he thinks is also a possibility. He says that if “a mile-high unicycle is logically impossible, she must give us some idea of where the contradiction lies, whether explicit or implicit” (Chalmers 1996; 96). The same burden falls on the person who wants to deny zombies. This argument shows that consciousness does not metaphysically or logically supervene on the physical and that consciousness must be non-physical (Chalmers 1996; 97). The phenomenal properties can differ without a difference in the physical properties and thus the phenomenal properties do not metaphysically or logically supervene on the physical properties.


Maybe the zombie argument is not convincing for a functionalist or a type-type theorist. Consider another argument of the inverted spectrum. The argument relies on some of the same intuitions as the zombie argument but the intuitions are much more localized. The zombie argument considers the whole physical identity of an entity with respects to phenomenal consciousness, while the inverted spectrum argument considers the function of the visual color spectrum and how it relates to experience. It seems possible that you can have two people who are identical to each other yet one of them has an inverted color experience. Person X has properly functioning vision (his brain is ordered in the proper way) and picks out apples, firetrucks, and strawberries as being red objects. This person experiences red. Person Y, on the other hand, picks out these same objects as being red, yet has the experience of green. Person Y has inverted vision. How can this be possible? It seems possible that we can change the brain structures in such a way to have this inversion. This argument is successful at showing that the function of person X can be completely identical to the function of person Y and yet both lead to two totally different experiences. If the functions are the same, why are the generated experiences fundamentally different? “Somebody might conceivably hold that inverted spectra but not zombies are logically possible. If this were the case, then the existence of consciousness could be reductively explained, but the specific character of particular conscious experiences could not be” (Chalmers 1996; 99-101).

On the left: A visual representation of the inverted spectrum. On the right: A zombie.

On the left: A visual representation of the inverted spectrum. On the right: A zombie.

Let us consider a final argument known as the Mary Argument. This argument involves a thought experiment. Imagine a neuroscientist named Mary. She is the leading expert in her field when it comes to her knowledge about how color operates, how our eyes pick up the light from color, and how our brain functions during that process. She knows all the physical facts about vision and the brain. But, as it turns out she has been raised in a black-and-white room. She has never experienced color. We can imagine her opening the door and leaving the black-and-white world and going into the world of color experience. Since she has never had any experience of color before, her entrance into the colored world will add more information to her knowledge about vision and the brain. Prior to opening that door, she knew all the physical facts about color but, after opening the door she learned something new – the way it feels to subjectively experience color (Chalmers 2003; 7). As a helpful analogy, consider the movie The Wizard of Oz. Dorothy grows up and lives in a black and white world her whole life. Yet, when she enters the world of Oz for the first time she learns something new about subjective experience of color. The Mary argument is similar to this, but it is different because Mary has full knowledge of all the physical color facts. This argument can be put as such:

  1. Mary knows all the physical facts.
  2. Mary does not know all the facts
  3. Conclusion: The physical facts do not exhaust all the facts. (Chalmers 2003; 7)


This argument shows that we cannot gain all the facts of the world merely by having a list of all the physical facts. Indeed, Richard Swinburne says that a full history of the world must include public facts and facts in which we have private access to (in this case, Mary’s subjective experience of color) (Swinburne 67-70).

Dorthy opening up the door and experiencing the colored Oz.

Dorthy opening up the door and experiencing the colored Oz.

We have established that these arguments minimally lead to a form of property dualism and that these arguments give us an explanatory bridge for the hard problem of consciousness. I do not believe that one can consistently hold a view that resembles Chalmers’s view. Since I still maintain that the three arguments are successful, I think that one must embrace a form of substance dualism. I have briefly explained this view earlier, but let me reiterate it again. Substance dualism is the view that there are two distinct substances (mental and physical substances) with respective properties and that these two substances interact with one another. Another entailment of this view is that the self is essentially a pure mental substance and not a physical substance. I am now going to argue that property dualism motivates towards substance dualism and that property dualism has more problems than substance dualism. I will argue that property dualism has some conceptual challenges. Moreover, I will give a negative and a positive argument against a form of property dualism, specifically, Chalmers’s view. Lastly, I will briefly examine some metaphysical constraints that may or may not be beneficial in determining one’s metaphysical framework.


Works Cited

Block, Ned. “Concepts of Consciousness.” Philosophy of Mind: Classical and Contemporary Readings. New York: Oxford UP, 2002. 206-18. Print.

Chalmers, David J. The Conscious Mind: In Search of a Fundamental Theory. New York: Oxford UP, 1996. Print.

Chalmers, David J. “Consciousness and Its Place in Nature.” Papers on Consciousness. N.p., 2003. Web. Apr.-May 2015. <;.

Chalmers, David J. “Facing Up to the Hard Problem of Consciousness.” Papers on Consciousness. N.p., 1995. Web. Apr.-May 2015. <;.

Swinburne, Richard. Mind, Brain, and Free Will. Oxford: Oxford UP, 2013. Print.


Can Property Dualism Have Its Consciousness and Experience it Too? Part I

Consciousness is puzzling. It is something we are immediately aware of, yet at the same time it is equally mysterious. We experience the world but it seems hard to grasp how we can explain our experience adequately to another person. Why do we have an experience of the world and why is this experience subjective? A metaphysical framework will be the main tool in how one approaches and explains the problem of consciousness. There are two broad views that one can adopt in addressing this question. The first is a physicalist view of consciousness. Physicalism is the thesis that human beings are only a physical thing with physical properties and that consciousness can be explained through purely physical processes in the brain. Historically, this view has also been called materialism but over the past hundred years the term physicalism has become more popular, though both can be used interchangeably. Dualism, which is the second view, posits two different things in the ontological framework. There are two positions of dualism in philosophy of mind – property dualism and substance dualism. Property dualism is the view that human beings are a physical substance which has physical properties and irreducible mental properties and that consciousness can be explained in terms of both these physical properties and mental properties. Property dualism treats these properties as being fundamentally different from one another. Substance dualism on the other hand, is the view that humans have both a physical substance – their body – and an immaterial substance – their soul. Under this view these two substances are distinct from one another and interact with one another in a two-way relation. This view also holds that human beings are essentially their soul and that when the body dies the soul can still continue to exist. Advocates of both forms of dualism argue that the physicalist picture is not adequate in explaining what consciousness is and how we have it. A handful of philosophers in the philosophy of mind have been adopting a property dualist view because of skepticism about physicalism’s explanatory power. In this paper I will show that arguments that lead to property dualism are correct as a critique of physicalism’s ability to give an explanatory bridge of consciousness, but I will argue that property dualism is an untenable middle ground position and pushes one towards a substance dualism.

We must first understand what physicalism is in order to understand the context of the critiques of it. I have stated that physicalism is the thesis that human beings are only a physical thing with physical properties and that consciousness can be explained through purely physical processes in the brain. There are different ways as to how the physicalist can address this explanation. Eliminativist theories do not regard consciousness as a thing to be explained because they deny its existence outright. More modest eliminativist views deny certain features of consciousness such as qualia (Gulick). “Qualia is plural for quale, which means a specific experiential quality – for example, what it is like to experience redness or blueness” (Moreland 257). Eliminativism does not regard consciousness as a viable conceptual scheme (Gulick). Behaviorism is the view that mental states can be merely characterized as behavior states. I can know the mental state of a person by observing their behavior. When someone pricks me with a pin, you can determine my pain by my reaction to the pin. Thus, behavior states can be used to explain conscious states (Moreland 250). A type-type identity theory treats physical states as being the same as mental states. This view takes a phenomenal experience such as seeing red as identical to a physical brain state. If mental states are identical to physical brain states then no explanation is needed as to how mental states emerge from physical states (Gulick). A functionalist physicalist theory sees consciousness as a function or role of the brain. This view relies on realizability in order to explain how mental states and physical states relate (Gulick). A common analogy to explain this view is the difference between computer hardware and software. Philosopher J.P. Moreland says that “this is similar to requiring that only some sort of physical hardware can be the realizer of functional roles specified in computer software.” Functionalism does not regard mental states as having intrinsic features but only extrinsic features by the roles they play within the organism (Moreland 249).

It is important to discuss the notion of supervenience in philosophy of mind and more importantly how it relates to functionalism. In his book Mind, Brain, and Free Will, Richard Swinburne says that “functionalists claim that science has shown that the only events in humans caused by input to sense-organs and causing behavioural output are brain events. Hence many brain events are events with functional properties which supervene on brain properties” (95) Terence Horgan defines supervenience as:

a determination relation between properties or characteristics of objects. The basic idea is this: properties of type A are supervenient on properties of type B if and only if two objects cannot differ with respect to their A-properties without also differing in their B-properties (150).


For example, “a utilitarian may urge that moral properties supervene on properties measuring human happiness.” So, if there is a change in the properties measuring human happiness, there is a change in the moral properties according to the utilitarian (Swinburne 22). It is important to have this definition of supervenience when discussing concepts in the philosophy of mind. Given these brief sketches of some physicalist pictures of consciousness, I will now show how other philosophers have responded to these views. Type-type and functionalist views are the two most popular of the four. Behaviorism is rejected by most physicalists, and eliminativism does not even enter the discussion on consciousness. Consequently, this paper will focus on the former two views.


Works Cited

Gulick, Robert Van. “Physicalist Theories.” Stanford University. Stanford University, 18 June 2004. Web. 27 May 2015. <;.

Horgan, Terence. “From Supervenience to Superdupervenience.” Philosophy of Mind: Classical and Contemporary Readings. New York: Oxford UP, 2002. 150-62. Print.

Moreland, James Porter, and William Lane. Craig. “Dualism and Alternatives to Dualism.” Philosophical Foundations for a Christian Worldview. Downers Grove, IL: InterVarsity, 2003. 228-66. Print.

Swinburne, Richard. Mind, Brain, and Free Will. Oxford: Oxford UP, 2013. Print.

Alvin Plantinga – Against Materialism

The debate over what consciousness is and how it interacts with the body is a debate in which both science and philosophy operate. Philosophers have generally referred to this debate as the mind-body problem. The two general views on how to confront this problem are materialism and dualism. “Materialism is the idea that human beings are material objects — brains, perhaps, or some part of the brain — without immaterial selves or souls” (Plantinga 3). Conversely, dualism is the view that human beings are comprised of an immaterial soul and a material body. Under this broad view, humans are not only their body; they are primarily a soul. Both of these views are metaphysical positions. If materialism is true then human beings are just one substance. If dualism is true then human beings are two substances – an immaterial substance and a material one. I will not be analyzing how these two substances are integrated in the human being. Some philosophers think that human beings are composites and not necessarily two substances. Analytic philosopher Alvin Plantinga puts forth two arguments against materialism in his essay. His argument strategy is to use the modal intuitions of possibility and impossibility in relation to the mind-body problem. I will argue that Plantinga is correct in his assessment of materialism and that his two arguments are valid and sound.

Plantinga’s first argument is called the replacement argument. He thinks is it possible for a person to exist when their body doesn’t. He does not argue that we can exist disembodied but rather he does argue that we could exist in a different body. If materialism is true, then I am a material object. I am most likely identical to my brain or some part of my body. It seems completely possible that I could exist while my body no longer exists. Plantinga says that if it is true that a person could still exist even when their body no longer exists, then that person and his body are not identical (4). This is true because of Leibniz’ Law, specifically the identity of indiscernibles. “This says that if A is strictly identical with B, then A and B have exactly the same properties” (Armstrong 3). If the modal properties are different, then those two things are not identical. In the case of me and my body, the modal properties are different. Plantinga imagines a situation where modern science has advanced so well that it can replace body parts extremely quickly. The process can replace all of his body parts. He also imagines that his old body is annihilated. All of this takes place while he is “reading the comic section of the newspaper” (Plantinga 5). Science says all the matter in our body is completely different from our old body some time ago. Plantinga thinks that accelerating the process seems possible regardless of cell assimilation (6). Cell assimilation is the time required for new cells to integrate into the body. Our bodies are constantly creating new cells and these cells assimilate through causal activities with other cells in the body. All that is required for this argument is the following (B standing for body): “It is possible that: the cells in B are replaced by other cells and the originals instantly annihilated while I continue to exist; and the replacement time for B and those cells is shorter than the assimilation time” (Plantinga 6).

Alvin Plantinga considers a few objections to his thought experiment. He responds to an objection from a “Star Trek” scenario where a person is beamed or teleported to a new location. The objector thinks that this thought experiment is analogous to Plantinga’s and thus it clearly shows that it’s possible that your body survives this type of replacement. Plantinga does not think that this thought experiment is analogous. His argument says that your old body is completely destroyed while the Star Trek thought experiment is just a disassembly and reassembly of your same body. Another objection says that persons are events, not necessarily a material substance. It is true that I am the same as my life – an event– in the actual world, but my life could have been different. There is no necessary identity with me and my life. It fails to get around the replacement argument (Plantinga 7-11). Plantinga’s argument does seem to be true. It does seem possible that I should exist in a different body while my former body is destroyed. As long as this is logically possible then materialism cannot be true since we are not necessarily identical to our body.

His second argument is also from a modal intuition but this time it is an argument from impossibility. The motivation behind offering this second argument is because some critics might not fully trust possibility intuitions. For this second argument he explains basic features of consciousness we all know to be true. All of us have first person experience of emotions. We all have desires and beliefs. All things being equal, we cannot be identical to anything that lacks these properties. The problem for materialism, and the main point of this argument, is consciousness itself. How can a material object have beliefs, desires, experiences of pain et cetera? (Plantinga 11-12). Plantinga cites Leibniz’ thought experiment on how this can be demonstrated. Leibniz asks us to imagine a machine that perceives, desires, and thinks. Imagine that this machine is the size of a mill – we can enter this machine. When we look into the machine, all we can see are parts that are causing these perceptions to happen. But the interaction of these mechanical parts does not show any content as to what the perception or belief is. This seems false because we know the content of our own minds. Therefore, Leibniz thinks that materialism cannot adequately explain the content of our minds (Plantinga 12). What are beliefs comprised of in a materialist perspective? The materialist would argue that these beliefs are events. These events are something that takes place in the neuron structure of your brain. These beliefs have propositional content. Plantinga jokingly uses the example that his “belief that naturalism is all the rage these days has as content the proposition Naturalism is all the rage these days (Plantinga 13). All beliefs must be able to express propositional content. This is problematic for materialism because, as Leibniz’ argument showed, neurons firing in the brain does not reveal any type of content. How can a set of neurons be related to a proposition? It seems impossible to see how material interactions could possess content of this sort. If they have no content they how can material beliefs be about anything? (Plantinga 15). One objection could be that computers have propositional knowledge. Computers are material objects that have wires, mother boards, and hard drives. We can store propositions on a computer such as “naturalism is all the rage these days” (Plantinga 16). Thus, the objection would show that material objects can contain content. But this does not follow since, in the example with the computer, the content has to be original and not derived from actual consciousness. We input the proposition into the computer; the computer does not think up the proposition on its own. Peter van Inwagen sees this as a difficulty for materialism. He thinks it is hard to account for beliefs and content under materialism but he also thinks that dualism is not better off. An immaterial substance interacting with a material substance is equally mysterious because we cannot have a mental image of an immaterial substance (Plantinga 17-18). Plantinga thinks that this is irrelevant because just because we cannot have a mental image of something does not mean it’s mysterious. We do not have mental images of numbers for example but it seems clear we can know what numbers are to some degree. We have an understanding of numbers. Peter makes the second point that materialist can at least have a representation of the interaction amongst the material parts while dualist cannot have one. Dualism implies the soul, which is a simple entity that is not comprised of parts (Plantinga 19-21). To ask for a representation of how the interaction takes place is to misunderstand the nature of the soul. It is to want a set of causes to explain the interaction. If the soul is a simple substance, then the interaction is direct. Plantinga concludes that consciousness is only mysterious when we think of it in materialist terms. He also concludes that his argument and rebuttals to objections show that a material thing cannot have beliefs or content (Plantinga 20-22).

Alvin Plantinga’s arguments are correct. It seems to me that both are valid and sound. The use of modal intuitions seems to be fair in his method of argumentation. I think it is clearly possible that I could exist while my body does not. This could be false in the actual world. Just because it is false in the actual world does not mean that it is false in all possible worlds. I can imagine a world in which it is true. The argument from impossibility seems to be even stronger than the first. It seems hard to see how a material object can be about something. Our brains are just neurons firing away that have no content of what the beliefs are. Both arguments against materialism are successful and show that dualism has more explanatory power over it.

I have shown both arguments Alvin Plantinga puts forth in his essay Against Materialism and have argued that they are both true. The importance of the mind-body debate is not only philosophical but also practical in how we view human beings. Questions of ontology effect how we think in all other branches of philosophy and life.

Works Cited

Armstrong, D. M. Universals: An Opinionated Introduction. Boulder: Westview, 1989. Print.

Plantinga, Alvin. “Against Materialism.” (n.d.): n. pag. Web. 21 Nov. 2014.   <>.

The Mind-Body Problem

For centuries philosophers have been debating over how the mind relates to the body. The two dominant positions on the philosophy of the mind are dualism and materialism. Dualism can be categorized into two types — property dualism and substance dualism — but this essay will focus on substance dualism only. Substance dualism is the belief that persons are comprised of both material and immaterial substances. The opposite view is materialism which states that people are merely material substances or objects and there are no immaterial mental states. Substances are ontological foundations for reality. This essay will defend and explain substance dualism, and will explain some of the problems for materialism.

Substance dualism is properly defined as the belief “that the brain is a physical object that has physical properties and the mind or soul is a mental substance that has mental properties” (Moreland 232). Early philosophers have been for the most part dualists. The Greeks believed that the soul would leave the body after death. Christian theologians and philosophers such as Aquinas and Augustine also held this same view. Other early philosophers such as the Gnostics saw matter as inherently and completely evil and the spirit entirely good. Sixteenth century philosopher Rene Descartes was one of the first to actually defend and articulate what dualism is. Descartes used a method of doubt in order to arrive at epistemological conclusions. His first level of doubt involved doubting the senses because of their fallibility. The second level was the possibility of being in a dream world, and the third and final level was on the basis that there could possibly be an evil genius controlling his thoughts and making him have false beliefs. At the end of this method of doubt, Descartes realizes that he can prove that he exists by making the statement “I am, I exist, is necessarily true each time that I pronounce it, or that I mentally conceive of it” (Kolak 46). He made a distinction between his thoughts and his brain. Descartes defined the mental thinking substance as “a thing which thinks” (Kolak 47). The Cartesian concept of dualism would be extremely significant in future definitions of dualism and how the two substances — mental and physical — are defined and explained.

Philosopher Alvin Plantinga defines materialism as “the idea that human beings are material objects—brains, perhaps, or some part of the brain—without immaterial selves or souls.” This would mean that the human is comprised of one substance. This substance is only physical and material. The mind exists as the brain and is not a different substance. In their work Philosophical Foundations for a Christian Worldview, philosophers J.P. Moreland and William Lane Craig make an observation about materialism. They say that “no material thing presupposes or requires reference to consciousness for it to exist or be characterized” ( Moreland 231). If materialism is true, does that mean consciousness does not really exist? It would appear as such. All mental activities exist in space and time and are based on this material substance.

There are several arguments supporting substance dualism and there are also several objections against it. The first of the arguments supporting dualism deals with awareness of the self. Persons have this awareness that they are not necessarily their body. They can introspectively realize that they have both physical and mental substances (Moreland 238). The second argument deals with first-person perspectives. People always have an awareness of themselves before anything else. All experiences a person feels come in the form of a first-person perspective. Materialism, on the other hand, says that all things can be described from a third-person point of view. However, this objection is almost impossible to defend since it is highly unlikely for one to describe the subjective moods and feelings completely of a person from a third-person statement (Moreland 239). The third argument to support dualism is that we have an unchanging personal identity. The body and the mind are constantly being changed but the person still realizes that he or she is the same person (Moreland 239). The final argument is regarding free-will. Dualism makes the best sense of free-will. We have an immaterial substance that is not subjugated under physical laws of nature. Thus our actions are not determined in any sort of way and we can make decisions freely. Free-will also helps in the area of ethics. If persons are determined to do whatever actions they do, then it is hard to make sense of any moral or ethical accountability.

Dualism has a few objections which will be discussed here. The first, and probably the strongest is called the problem of interaction. The problem with dualism is the fact that no one knows how the mind and body interact. Garrett Thomson, professor of philosophy at Wooster College, says “first, we can never have direct experience of this interaction. Second, the two types of substance, mind and matter, are utterly different in kind, and this makes interaction between them obscure, placing some doubt on the whole idea of dualism” (47). J.P. Moreland responds to this claim basically by saying that we do not need to know how the two substances interact. There are many things we know that interact with each other but we do not know exactly how they do. Moreland also says that it might be impossible to answer this question of how the substances interact. He states that by asking how the interaction is fulfilled, one is asking for some cause in-between the two substances. But the interaction between the two might just be a direct interaction and thus this problem of interaction is defeated (243-244). The second objection against dualism deals with Ockham’s razor. Ockham’s razor says that the simplest explanation is generally the best explanation. Dualism is positing two substances rather than one and thus is less likely to be true. The dualist is not multiplying entities beyond what is necessary because they are using it to explain things which materialism cannot. Ockham’s razor is merely just a general rule to find truth in causes and is meant to limit causes to only the amount necessary. But this seems irrelevant for the person who accepts dualism because dualism is not creating unnecessary causes (Moreland 244-245). The last objection is the problem of other minds. If dualism is true, then one cannot actually know if other minds exist because they are immaterial (Thomson 48-49). One could be taken to the conclusion that solipsism — the belief that there is only one mind in reality — is true.

Materialism has some arguments supporting it and many arguments against it. The main one is based off of scientific naturalism. If scientific naturalism is true then there is nothing immaterial and only matter exists. This would support the view that materialism is true. But this is just a presupposition that scientific naturalism is true. John Searle recognizes this by saying that the “acceptance of the current [physicalist] views is motivated not so much by an independent conviction of their truth as by a terror of what are apparently the only alternatives.” Searle goes on by saying dualism is regarded as “unscientific” (Moreland 249). The second argument for materialism is based off Ockham’s razor, but that has already been addressed in this essay. The third argument has to do with the concept of split brains. The brain is divided into two hemispheres. These two parts to the brain are so different from one another yet they interact with each other. “The split-brain patient seems to have two minds. What the left brain learns and thinks is unknown to the right brain, and vice versa” (Split-Brain). This seems to support the belief that all humans are mere brains. When the brain is split the two hemispheres can work completely independent of each other. In some patients the left hand does things completely contrary to what the right hand is doing (Split-Brain).  This would possibly entail that our brains are who we actually are. We cannot use our mental substance to control each side of the brain. Maybe the mental substance is oddly dependent on the physical substance and vice versa.

There are several objections to materialism. The first of these is the problem of the inverted qualia. This problem deals with how we see color. It is impossible to actually know how one sees red or blue. For a person might see a blue truck as a blue truck yet another person might see it as a red truck (Inverted). If this is possible wouldn’t that defeat materialism? The second objection comes from John Searle’s Chinese room thought experiment. The thought experiment involves a person who is locked in a room and does not know Chinese. He is given a rule book on how to formulate these symbols (the book is in English). The formulation of these symbols is based on their syntax and not on their semantics. Let’s say people outside the room are giving this person more symbols in the form of questions and also another rule book on how to pass these questions back to the people. Eventually, all the responses would come back as if the person knew Chinese when in reality he didn’t. This is an example of how computer programs act. They make completely rational responses yet they have no idea why or how they did it. This shows that there’s something more than just a material substance for the person (Moreland 257-258).

The last objection involves determinism. If materialism states that all humans are physical brains then determinism has to be true. Cause and effect is the fundamental law of nature as far as matter is concerned. But determinism is self-refuting. H.P. Owen states that “determinism is self-stultifying. If my mental processes are totally determined, I am totally determined either to accept or to reject determinism. But if the sole reason for my believing or not believing X is that I am causally determined to believe it I have no ground for holding that my judgment is true or false” (Moreland 241). Determinism seems to be a big hurdle for the person who accepts materialism.

Substance dualism is in every way superior to materialism for a few reasons. It makes the best sense of the subjectivity of things such as color, taste, and first-person experience (which cannot be explained in third-person statements). It also helps with maintaining ethics and free-will. Without free-will it would be hard how anyone would make sense of the world or even their own beliefs. And all moral responsibility would seem to completely dissipate if free-will does not exist. Materialism on the other hand is defeated by its determinism and the Chinese room argument. The arguments against dualism seem to not carry as much weight as the arguments against materialism. Materialism only seems to be the more current popular view because of the presupposition it holds — namely, scientific naturalism. The mind-body problem might not be resolved until scientists and philosophers alike are willing to accept the possibility that scientific naturalism might be false.

Works Cited

“Inverted Qualia.” Stanford Encyclopedia of Philosophy. 28 Mar. 2010 <>.

Kolak, Daniel, and Garrett Thomson. The Longman standard history of philosophy. New York: Pearson/Longman, 2006.

Moreland, James Porter, and William Lane. Craig. Philosophical foundations for a Christian worldview. Downers Grove, Ill: InterVarsity P, 2004.

Plantinga, Alvin. Against Materialism. Ms. University of Notre Dame. Http:// 27 Mar. 2010 <>.

“Split- Brain Behavior.” Serendip’s Exchange. 28 Mar. 2010 <>.

Thomson, Garrett. Bacon to Kant: An Introduction to Modern Philosophy. 2nd ed. Long Grove, Illinois: Waveland P, Inc., 2002.