In chapter 3, I defended property dualism and concluded that consciousness is, indeed, non-physical. In this chapter, I will argue for substance dualism, the view that the owner of consciousness—the soul or self—is immaterial. Substance dualists are also property dualists, because substance dualists believe that both the ego and consciousness itself are immaterial. But one can be a mere property dualist without being a substance dualist if one accepts the immateriality of consciousness but holds that its owner is the body or, more likely, the brain. In contrast to mere property dualism, substance dualists hold that the brain is a physical thing that has physical properties, and the mind or soul is a mental substance that has mental properties. When I am in pain, the brain has certain physical properties (electrical, chemical), and the soul or self has certain mental properties (the conscious awareness of pain). The soul is the possessor of its experiences. It stands behind and above them and remains the same throughout my life. The soul and the brain can interact with each other, but they are different objects with different properties.
Currently, there are three main forms of substance dualism. First, there is *Cartesian dualism, according to which the mind is a substance with the ultimate capacities for consciousness, and it is connected to its body by way of a causal relation (that is, my body is mine because I can cause things to happen to it and vice versa).1 Second, there is *Thomistic substance dualism, one important version of which takes the soul to be broader than the mind in containing not merely the capacities for consciousness, but also those which ground biological life and functioning. On this view, the (human) soul diffuses, informs (gives form to), unifies, animates, and makes human the body. The body is not a physical substance, but rather, an ensouled physical structure such that if it loses the soul, it is no longer a human body in a strict, philosophical sense.2 Instead, it becomes a corpse. According to the third form, *emergent dualism, a substantial, spatially extended, immaterial self emerges from the functioning of the brain and nervous system, but once it emerges, it exercises its own causal powers and continues to be sustained by God after death.3 As interesting as this intramural debate is, for our purposes we will set it aside and simply argue for that which all three positions hold in common: the self or ego is an immaterial substance that bears consciousness.
At least five arguments have been offered in the recent literature for some form of substance dualism.
Our Basic Awareness of the Self
Stewart Goetz has advanced the following type of argument for the nonphysical nature of the self, which I have modified:4
(1) I am essentially an indivisible, simple spiritual substance.
(2) Any physical body is essentially a divisible or complex entity (any physical body has spatial extension or separable parts).
(3) The law of identity pertains (if x is identical to y, then whatever is true of x is true of y, and vice versa).
(4) Therefore, I am not identical with my (or any) physical body.
(5) If I am not identical with a physical body, then I am a soul.
(6) Therefore, I am a soul.
Premise (2) is pretty obvious, and (5) is commonsensical. The body and brain are complex material objects made of billions of parts—atoms, molecules, etc. Premise (3) is the law of identity I introduced in chapter 1. Regarding premise (1), we know it is true by introspection. When we enter most deeply into ourselves, we become aware of a very basic fact presented to us: We are aware of our own self (ego, I, center of consciousness) as being distinct from our bodies and from any particular mental experience we have, and as being an uncomposed, spatially unextended, simple center of consciousness. In short, we are just aware of ourselves as simple, conscious things. This fundamental awareness is what grounds my *properly basic belief (a rational belief that is not inferred from other beliefs) that I am a simple center of consciousness. On the basis of this awareness, and premises (2) and (3), I know that I am not identical to my body or my conscious states; rather, I am the immaterial self that has a body and a conscious mental life.
An experiment may help convince you of this. Right now I am looking at a chair in my office. As I walk toward the chair, I experience a series of what are called phenomenological objects or chair representations. That is, I have several different chair experiences that replace one another in rapid succession. As I approach the chair, my chair sensations vary. If I pay attention, I am also aware of two more things. First, I do not simply experience a series of sense-images of a chair. Rather, through self-awareness, I also experience the fact that it is I myself who has each chair experience. Each chair sensation produced at each angle of perspective has a perceiver who is I. An “I” accompanies each sense experience to produce a series of awarenesses—“I am experiencing a chair sense-image now.”
I am also aware of the basic fact that the self that is currently having a fairly large chair experience (as my eyes come to within twelve inches of the chair) is the very same self as the one who had all of the other chair experiences preceding this current one. Through self-awareness, I am aware of the fact that I am an enduring self who was and is (and will be) present as the owner of all the experiences in the series.
These two facts—I am the owner of my experiences, and I am an enduring self—show that I am not identical to my experiences. Rather, I am the conscious thing that has them. I am also aware of myself as a simple, uncomposed, and spatially unextended center of consciousness. In short, I am a mental substance. Moreover, I am “fully present” throughout my body, though not identical to any part of it; if my arm is cut off, I do not become four-fifths of a self. My body and brain are divisible and can be present in percentages (there could be 80 percent of a brain present after an operation). But I am an all-or-nothing kind of thing. I am not divisible; I cannot be present in percentages.
Consider the following argument:
(1) If I were a physical object (e.g., a brain or body), then a third-person physical description would capture all the facts that are true of me.
(2) But a third-person physical description does not capture all the facts that are true of me.
(3) Therefore, I am not a physical object.
(4) I am either a physical object or a soul.
(5) Therefore, I am a soul.
A complete physical description of the world would be one in which everything would be exhaustively described from a third-person point of view in terms of objects, properties, processes, and their spatiotemporal locations. For example, a description of an apple in a room would go something like this: “There exists an object three feet from the south wall and two feet from the east wall, and that object has the property of being red, round, of weighing 3.5 ounces,” and so on.
The *first-person point of view is the vantage point that I use to describe the world from my own perspective. Expressions of a first-person point of view utilize what are called indexicals—words like “I,” “here,” “now,” “there,” “then.” Here and now are where and when I am; there and then are where and when I am not. Indexicals refer to me. “I” is the most basic indexical, and it refers to my self that I know by acquaintance with my own acts of self-awareness. I am immediately aware of my own self and I know to whom “I” refers when I use it: it refers to me as the conscious owner of my body and mental states.
According to a widely accepted form of physicalism, there are no irreducible, privileged, first-person perspectives. Everything can be exhaustively described in an object language from a third-person perspective. A physicalist description of me would say, “There exists a body at a certain location that is five feet eight inches tall, weighs 160 pounds,” and so forth. The property dualist would add a description of the properties possessed by that body, such as “The body is feeling pain,” or “It is thinking about lunch.”
But no amount of third-person descriptions captures my own subjective, first-person acquaintance of my own self in acts of self-awareness. In fact, for any third-person description of me, it would always be an open question as to whether the person described in third-person terms was the same person as I am. I do not know myself because I know some third-person description of a set of mental and physical properties that apply to me (“So, the body is five-feet-eight-inches, 160 pounds, and is thinking about lunch? I think that’s me.”). Instead I know myself as a self immediately through being acquainted with my own self in an act of self-awareness. I can express that self-awareness by using the term I.
I refers to my own substantial soul. It does not refer to any mental property or bundle of mental properties I am having, nor does it refer to any body described from a third-person perspective. I is a term that refers to something that exists, and I does not refer to any object or set of properties described from a third-person point of view. Rather, I refers to my own self with which I am directly acquainted and which, through acts of self-awareness, I know to be the substantial, uncomposed possessor of my mental states and my body.
A related argument has been offered by William Hasker:
(1) If I am a physical object (e.g., a brain or a body), I do not have a unified visual field.
(2) I do have a unified visual field.
(3) Therefore, I am not a physical object.
(4) I am either a physical object or a soul.
(5) Therefore, I am a soul.
To grasp the argument, consider one’s awareness of a complex fact, say, one’s own visual field consisting of awareness of several objects at once, including a number of different surface areas of each object. Now, one may claim that such a unified awareness of one’s visual field consists in the fact that there are a number of different physical parts, each of which is aware only of part of and not the whole of the complex fact. Indeed, this is exactly what physicalists say. We now know that when one looks at an object, different regions of the brain process different electrical signals that are associated with different aspects of the object (e.g., its color, shape, size, texture, location).5 However, this claim will not work, because it cannot account for the fact that there is a single, unitary awareness of the entire visual field.6 There is no region in the brain that “puts the object back together into a unified whole.” Apart from a unifying consciousness, our daily lives would consist of a series of unconnected perceptions and images completely lacking in coherence. Only a single, uncomposed mental substance can account for the unity of one’s visual field or, indeed, the unity of consciousness in general.
The core of the modal argument for the soul is fairly simple: I am possibly disembodied (I could survive without my brain or body); my brain or body are not possibly disembodied (they could not survive without being physical); so I am not my brain or body. I am either a soul or a brain or a body, so I am a soul. Let’s elaborate on the argument.
Thought experiments such as this one have rightly been central to debates about personal identity. For example, we are often invited to consider a situation in which two people switch bodies, brains, or personality traits, or in which a person exists disembodied. In these thought experiments, someone argues in the following way: Because a certain state of affairs S (e.g., Smith existing disembodied) is conceivable, this provides justification for thinking that S is metaphysically possible. Now if S is possible, then certain implications follow about what is/is not essential to personal identity (e.g., Smith is not essentially a body).
We all use conceiving as a test for possibility/impossibility throughout our lives. I know that life on other planets is possible (even if I think it is highly unlikely or downright false) because I can conceive it to be so. I am aware of what it is to be living and to be on earth and I conceive no necessary connections between these two properties (surely life could exist on other planets besides this one). On the other hand, I know square circles are impossible because they are inconceivable given my knowledge of being square and being circular. To be sure, judgments that a state of affairs is possible/impossible grounded in conceivability are not infallible. They can be wrong. Still, they provide strong evidence for genuine possibility/impossibility. In light of this, I offer the following criterion:
For any entities x and y, if I have good grounds for believing I can conceive of x existing without y (e.g., a dog without being colored brown) or vice versa, then I have good grounds for believing x (being brown) is not essential or identical to y (being a dog) or vice versa.
Let us apply these insights about conceivability and possibility to the modal argument for substance dualism. We can expand the argument outlined above as follows:7
(1) The law of identity: If x is identical to y, then whatever is true of x is true of y and vice versa.
(2) I can strongly conceive of myself as existing disembodied. (For example, I have no difficulty believing that out-of-body near-death experiences are possible; that is, they could be true.)
(3) If I can strongly conceive of some state of affairs S (e.g., my disembodied existence) that S possibly obtains, then I have good grounds for believing that S is possible.
(4) Therefore, I have good grounds for believing of myself that it is possible for me to exist and be disembodied.
(5) If some entity x (for example, my self) is such that it is possible for x to exist without y (for example, my brain or body), then (i) x (my self) is not identical to y (my brain or body) and (ii) y (my brain or body) is not essential to x (me).
(6) My body (or brain) is not such that it is possible to exist disembodied, i.e., my body (or brain) is essentially physical.
(7) Therefore, I have good grounds for believing of myself that I am not identical to my body (or brain) and that my physical body is not essential to me.
A parallel argument can be advanced in which the notions of a body and disembodiment are replaced with the notions of physical objects. So understood, the argument would imply the conclusion that I have good grounds for thinking that I am not identical to a physical object, nor is any physical object essential to me. A parallel argument can also be developed to show that possessing the ultimate capacities of sensation, thought, belief, desire, and volition are essential to me, implying that I am a substantial soul or mind and I could not exist without the ultimate capacities of consciousness.
I cannot undertake a full defense of the argument here, but it would be useful to say a bit more regarding (2). There are a number of things about ourselves and our bodies of which we are aware that ground the conceivability expressed in (2). I am aware that I am unextended (I am “fully present” at each location in my body, as Augustine claimed; I occupy my body as God occupies space by being fully present throughout it); I am not a complex aggregate made of substantial parts, nor am I the sort of thing that can be composed of physical parts; rather, I am a basic unity of inseparable faculties (of mind, volitions, emotion, etc.) that sustains absolute sameness through change; and I am not capable of gradation (I cannot become two-thirds of a person).8
In near-death experiences, people report themselves to have been disembodied. They are not aware of having bodies in any sense. Rather, they are aware of themselves as unified egos that have sensations, thoughts, and so forth. Moreover, Christians who understand the biblical teaching that God and angels are bodiless spirits also understand by direct introspection that they are like God and angels in the sense that they are spirits with some of the same sorts of powers God and angels have (e.g., to think rationally, to make moral judgments) but that they also have bodies. In addition, the New Testament teaching on the intermediate state is intelligible in light of what they know about themselves and it implies that we will and, therefore, can exist temporarily without our bodies. In 2 Corinthians 12:1–4, Paul asserts that he may actually have been disembodied. Surely part of the grounds for Paul’s willingness to consider this a real possibility was his own awareness of his nature through introspection, his recognition of his similarity to God and angels in this respect, and his knowledge of biblical teaching. All of the factors discussed above imply that people can conceive of themselves as existing in a disembodied state, and they provide grounds for thinking that this is a real possibility (even if it turns out to be false—though, of course, I do not think it is). If such disembodiment is even possible, then one cannot be one’s body, nor is one’s body essential to him.
Consider the following argument:
(1) If I am a physical object (e.g., a brain or a body), then I do not have free will.
(2) But I do have free will.
(3) Therefore, I am not a physical object.
(4) I am either a physical object or a soul.
(5) Therefore, I am a soul.
When I use the term free will, I mean what is called libertarian freedom. I can literally choose to act or refrain from acting. No circumstances exist that are sufficient to determine my choice. My choice is up to me. I act as an agent who is the ultimate originator of my own actions. Moreover, my reasons for acting do not partially or fully cause my actions; I myself bring about my actions. Rather, my reasons are the teleological goals or purposes for the sake of which I act. If I get a drink because I am thirsty, the desire to satisfy my thirst is the end for which I myself act freely. I raise my arm in order to vote.
If physicalism is true, then human free will does not exist. Instead, determinism is true.9 If I am just a physical system, there is nothing in me that has the capacity to freely choose to do something. Material systems, at least large-scale ones, change over time in deterministic fashion according to the initial conditions of the system and the laws of chemistry and physics. A pot of water will reach a certain temperature at a given time in a way determined by the amount of water, the input of heat, and the laws of heat transfer.
Now, when it comes to morality, it is hard to make sense of moral obligation and responsibility if determinism is true. They seem to presuppose freedom of the will. If I “ought” to do something, it seems to be necessary to suppose that I can do it, that I could have done otherwise, and that I am in control of my actions. No one would say that I ought to jump to the top of a fifty-floor building and save a baby, or that I ought to stop the American Civil War in this present year, because I do not have the ability to do either. If physicalism is true, I do not have any genuine ability to choose my actions. Further, free acts seem to be teleological. We act for the sake of goals or ends. If physicalism (or mere property dualism) is true, there is no genuine teleology and, thus, no libertarian free acts.
It is safe to say that physicalism requires a radical revision of our commonsense notions of freedom, moral obligation, responsibility, and punishment. On the other hand, if these commonsense notions are true, physicalism is false.
The same problem besets mere property dualism. There are two ways for property dualists to handle human actions. First, some property dualists are epiphenomenalists (a term we encountered in chapter 3). A person is a living physical body having a mind, the mind consisting, however, of nothing but a more or less continuous series of conscious or unconscious states and events that are the effects but never the causes of bodily activity. Put another way, when matter reaches a certain organizational complexity and structure, as is the case with the human brain, then matter produces mental states like fire produces smoke, or the structure of hydrogen and oxygen in water produces wetness. The mind is to the body as smoke is to fire. Smoke is different from fire (to keep the analogy going, the physicalist would identify the smoke with the fire or the functioning of the fire), but fire causes smoke, not vice versa. The mind is a by-product of the brain that causes nothing; the mind merely “rides” on top of the events in the brain. Hence, epiphenomenalists reject free will since they deny that mental states cause anything. A second way that property dualists handle human action is through a notion called *event-event causation.10 To understand event-event causation, consider a brick that breaks a glass. The cause in this case is not the brick itself (which is a substance), but an event, namely, the brick’s being in a certain state—a state of motion. And this event (the brick’s being in a state of motion) was caused by a prior event, and so on. The effect is another event, namely, the glass’s being in a certain state—breaking. Thus, one event—the moving of a brick—causes another event to occur—the breaking of the glass. Further, according to event-event causation, whenever one event causes another, there will be some deterministic or probabilistic law of nature that relates the two events. The first event, combined with the laws of nature, is sufficient to determine or fix the chances for the occurrence of the second event.
Agent action, on the other hand, is an important part of an adequate libertarian account of freedom of the will. One example of agent action is this typical case: my raising my arm. When I raise my arm, I, as a substance, simply act by spontaneously exercising my active powers. I raise my arm; I freely and spontaneously exercise the powers within my substantial soul and simply act. No set of conditions exists within me that is sufficient to determine that I raise my arm. Moreover, this substantial agent is characterized by the power of active freedom, conscious awareness, the ability to think, form goals and plans, to act teleologically (for the sake of goals), and so forth. Such an agent is an immaterial substance and not a physical object, which lacks these abilities. Thus, libertarian freedom is best explained by a substance dualism that involves agent action, and not by physicalism or mere property dualism that lacks such action.
Unfortunately for property dualists, event-event causation is deterministic. Why? For one thing, there is no room for an agent, an ego, an “I” to intervene and contribute to one’s actions. On this view, I do not produce the action of raising my arm; rather, a state of desiring to raise an arm is sufficient to produce the effect. There is no room for my own self, as opposed to the mental states within me, to act.
Moreover, all the mental states within me (my states of desiring, willing, hoping) are states that were deterministically caused (or had their chances fixed) by prior mental and physical states outside of my control, plus the relevant laws. “I” become a stream of states/events in a causal chain that merely passes through me. Each member of the chain determines that the next member occurs.
In summary, then, property dualism denies libertarian freedom because it adopts either epiphenomenalism or event-event causation. Thus, mere property dualism, no less than physicalism, is false, given the truth of a libertarian account of free will, moral ability, moral responsibility, and punishment. Our commonsense notions about moral ability, responsibility, and punishment are almost self-evident. We all operate toward one another on the assumption that they are true (and these commonsense notions seem to assume libertarian free will). However, if physicalism or property dualism is true, we will have to abandon and revise our commonsense notions of moral ability, responsibility, and punishment because free will is ruled out.
Consider the following argument:
(1) If something is a physical object composed of parts, it does not survive over time as the same object if it comes to have different parts.
(2) My body and brain are physical objects composed of parts.
(3) Therefore, my body and brain do not survive over time as the same objects if they come to have different parts.
(4) My body and brain are constantly coming to have different parts.
(5) Therefore, my body and brain do not survive over time as the same objects.
(6) I do survive over time as the same object.
(7) Therefore, I am not my body or my brain.
(8) I am either a soul or a body or a brain.
(9) Therefore, I am a soul.
Premise (2) is commonsensically true. Premise (4) is obviously true as well. Our bodies and brains are constantly gaining new cells and losing old ones, or at least gaining new atoms and molecules and losing old ones. So understood, bodies and brains are in constant flux. I will assume that (8) represents the only live options for most people. This leaves the key premises (1) and (6).
Let’s start with (1). Why should we believe that ordinary material objects composed of parts do not remain the same through part replacement?11 To see why this makes sense, consider five scattered wooden boards, which we’ll label a–e, each located in a different person’s backyard. Commonsensically, it doesn’t seem like the boards form an object. They are just isolated boards. Now, suppose we collected those boards and put them in a pile with the boards touching each other. We would now have, let us suppose, an object called a pile or heap of boards. The heap is a weak object indeed, and the only thing unifying it would be the spatial relationships between and among a–e. They are in close proximity and are touching each other. Now, suppose we took board b away and replaced it with a new board f to form a new heap consisting of a, c–f. Would our new heap be the same as the original heap? Clearly not, because the heap is just the boards and their relationships to each other, and we have a new board and a new set of relationships. What if we increased the number of boards in the heap to one thousand? If we now took one board away and replaced it with a new board, we would still get a new heap. The number of boards does not matter.
Now imagine that we nailed our original boards a-e together into a makeshift raft. In this situation, the boards are rigidly connected such that they do not move relative to each other; instead, they all move together if we pick up our raft. If we now took board b away and replaced it with board f, we would still get a new object. It may seem odd, but if we took board b away and later put it back, we would still have a new raft because the raft is a collection of parts and bonding relationships to each other. Thus, even though the new raft would still have the same parts (a–e), there would be new bonding relationships between b and the board or boards to which it is attached.
Now think of a cloud. From a distance, it looks like a solid, continuous object. But if you get close to it, say on a plane flight, it becomes evident that it is a very loose collection of water droplets. The cloud is like the heap of boards or the raft. If new droplets are added and some removed, it is, strictly speaking, not the same cloud.
Now, consider our bodies and brains, which are physical objects composed of billions of parts. From our daily vantage point, they appear to be solid, continuous objects. But if we could shrink down to the level of an atom, we would see that, in reality, they are like a cloud—gappy, largely containing empty space, and composed of billions of atoms (forming molecules and cells) that stand in various bonding relations between and among themselves. If we were to take a part away and replace it, we would have a new object. The body and brain are like the cloud or our raft. Besides the parts and the relationships among them, there is nothing in the body or brain to ground its ability to remain the same through part replacement. This is the fundamental insight behind the view that the body and brain cannot remain the same if there is part alteration.12 Since the body and brain are constantly changing parts and relationships, they are not the same from one moment to the next in a strict philosophical sense (though, for practical day-to-day purposes, we regard them as the same in a loose, popular sense).
What about premise (6)? Why should we think we survive as the same object over time? Suppose you are approaching a brown table and in three different moments of introspection you attend to your own awarenesses or experiences of the table. At time t1 you are five feet from the table and you experience a slight pain in your foot (P1), a certain light brown table sensation (S1) from a specific place in the room, and a specific thought that the table seems old (Th1). A moment later at t2 when you are three feet from the table you experience a feeling of warmth (F1) from a heater, a different table sensation (S2) with a different shape and slightly different shade of brown than that of S1, and a new thought that the table reminds you of your childhood desk (Th2). Finally, a few seconds later (t3), you feel a desire to have the table (D1), a new table sensation from one foot away (S3), and a new thought that you could buy it for less than twenty-five dollars (Th3).
In this series of experiences, you are aware of different things at different moments. However, at each moment of time, you are also aware that there is a self at that time that is having those experiences and that unites them into one field of consciousness. Moreover, you are also aware that the very same self had the experiences at t1, t2, and t3. Finally, you are aware that the self that had all of the experiences is none other than you yourself. This can be pictured as follows:
Through introspection, you are aware that you are the self that owns and unifies your experiences at each moment of time and that you are the same self that endures through time. This is pretty obvious to most people. When one hums a tune, one is simply aware of being the enduring subject that continues to exist during the process. This is a basic datum of experience.
Moreover, fear of some painful event in the future or fear of blame and punishment for some deed done in the past appear to make sense only if we implicitly assume that it is literally I myself who will experience the pain or who was the doer of the past deed. If I do not remain the same through time, it is hard to make sense of these cases of fear and punishment. We would not have such fear or merit such punishment if the person in the future or past merely resembled my current self in having similar memories, psychological traits, or a body spatio-temporally continuous with mine or that had many of the same parts as my current body.13
Finally, some have argued that to realize the truth of any proposition or even entertain it as meaningful, the very same self must be aware of its different parts (e.g., those expressed by the associated sentence’s subject, verb, and predicate). If one person-stage contemplated the subject, another stage the verb, and still another the predicate, literally no self would persist to think through and grasp the proposition as a whole.
For these and other reasons, we are warranted in believing that the I or self survives over time as the same object.14
If human beings have souls, then what are they like? How are spirit, mind, and will related to the soul? Are there such things as animal souls and, if so, are they different from the human soul? In the rest of this chapter we will tackle these questions.
The soul is a very complicated thing with an intricate structure. In order to understand that structure, we need to grasp two important issues: the different types of states within the soul and the notion of a faculty of the soul. The soul is a substantial, unified reality that informs (gives form to) its body. The soul is to the body like God is to space—it is fully “present” at each point within the body. Further, the soul and body relate to each other in a cause-effect way. For example, if I worry in my soul, my brain chemistry will change; if I will to raise my arm in my soul, the arm goes up. If I intake certain chemicals into my body (medication, etc.), my soul may be affected and my mood or feelings may change. The soul also contains various mental states within it, for example, sensations, thoughts, beliefs, desires, and acts of will. This is not as complicated as it sounds. Water can be in a cold or a hot state. Likewise, the soul can be in a feeling or thinking state.
Let us review the different states of consciousness that take place within the soul. As we have already seen, there are at least five different states contained in the soul. A sensation is a state of awareness, a mode of consciousness, such as a conscious awareness of sound or pain. A visual sensation like an experience of a tree is a state of the soul, not a state of the eyeballs. The eyes do not see. I (my soul) see with or by means of the eyes. A *thought is a mental content that can be expressed in an entire sentence and that only exists while it is being thought. Some thoughts logically imply other thoughts. For example, “All whales are mammals” entails “This whale is a mammal.” If the former is true, the latter must also be true. Some thoughts don’t entail, but merely provide evidence for other thoughts. A *belief is a person’s view, accepted to varying degrees of strength, of how things really are. If a person has a belief (e.g., that it is raining), then that belief serves as the basis for the person’s tendency to act on that belief (e.g., one gets an umbrella). At any given time, one can have many beliefs that are not currently being contemplated. A *desire is a certain inclination to do, have, avoid, or experience certain things. Desires are either conscious or such that they can be made conscious through certain activities, for example, through therapy. An *act of will is a volition or choice, an exercise of power, an endeavoring to do a certain thing, usually for the sake of some purpose or end.
In addition to its states, at any given time the soul has a number of capacities that are not currently being actualized or utilized. To understand this, consider an acorn. The acorn has certain actual characteristics or states—a specific size or color. It also has a number of capacities or potentialities that could become actual if certain things happen. For example, the acorn has the capacity to grow a root system or change into the shape of a tree. Likewise, the soul has capacities. I have the ability to see color, think about math, or desire ice cream even when I am asleep and not in the actual states just mentioned.
Capacities come in hierarchies. There are first-order capacities, second-order capacities to have these first-order capacities, and so on, until ultimate capacities are reached. For example, if I can speak English but not Russian, then I have the first-order capacity for English as well as the second-order capacity to have this first-order capacity (which I have already developed). I also have the second-order capacity to have the capacity to speak Russian, but I lack the first-order capacity to do so. Higher order capacities are realized by the development of lower-order capacities under them. An acorn has the ultimate capacity to draw nourishment from the soil, but this can be actualized and unfolded only by developing the lower capacity to have a root system, then developing the still lower capacities of the root system.
The adult human soul has literally thousands of capacities within its structure. But the soul is not just a collection of isolated, discrete, randomly related internal capacities. Rather, the various capacities within the soul fall into natural groupings called *faculties. In order to get hold of this, think for a moment about this list of capacities: the ability to see red, see orange, hear a dog bark, hear a tune, think about math, think about God, desire lunch, desire a family. The ability to see red is more closely related to the ability to see orange than it is to the ability to think about math. We express this insight by saying that the abilities to see red or orange are parts of the same faculty—the faculty of sight. The ability to think about math is a capacity within the thinking faculty. In general, a faculty is a “compartment” of the soul that contains a natural family of related capacities.
We are now in a position to map out the soul in more detail. All of the soul’s capacities to see are part of the faculty of sight. If my eyeballs are defective, then my soul’s faculty of sight will be inoperative just as a driver cannot get to work in his car if the spark plugs are broken. Likewise, if my eyeballs work but my soul is inattentive—say, I am daydreaming—then I won’t see what is before me either. The soul also contains faculties of smell, touch, taste, and hearing. Taken together, these five are called sensory faculties of the soul. The will is a faculty of the soul that contains my abilities to choose. The emotional faculty of the soul contains one’s abilities to experience fear, love, and so forth.
Two additional faculties of the soul are of crucial importance. The *mind is that faculty of the soul that contains thoughts and beliefs along with the relevant abilities to have them. It is with my mind that I think and my mind contains my beliefs. The *spirit is that faculty of the soul through which the person relates to God (Ps. 51:10: Rom. 8:16; Eph. 4:23).15 Before the new birth, the spirit is real and has certain abilities to be aware of God. But most of the capacities of the unregenerate spirit are dead and inoperative. At the new birth, God implants new capacities in the spirit. These fresh capacities need to be nourished and developed so they can grow.
It is sometimes a surprise to people to learn that the Bible teaches that animals, no less than humans, have souls. In the Old Testament, nephesh (soul) and ruach (spirit) are used of animals in Genesis 1:30 and Ecclesiastes 3:21, respectively. In the New Testament, psuche (soul) is used of animals in Revelation 8:9. Moreover, it is a matter of common sense that animals are not merely unconscious machines. Rather, they are conscious living beings with sensations, emotions (like fear), desires, and, at least for some animals, thoughts and beliefs. The history of Christian teaching is widely united in affirming the existence of the “souls of men and beasts” as it has sometimes been put. But what is the animal soul like? Let us consider this question.
How do we decide what an animal’s soul is like? Obviously, we cannot inspect it directly. We cannot get inside an animal’s conscious life and just look at its internal states. The best approach seems to be this: Based on our direct awareness of our own inner lives, we should attribute to animals by analogy those states that are necessary to account for the animal’s behavior, nothing more and nothing less.16 For example, if a dog steps on a thorn and then howls and holds up its paw, we are justified in attributing to the dog the same sort of state that happens in us just after we experience such a stick. The dog feels pain. Now the dog may also be having thoughts about his unfortunate luck in stepping on the thorn, but there is no adequate evidence for this if we stick to what we observe about the dog’s behavior. Such an attribution would be unjustified.
An interesting implication of this approach is that as we move down the animal chain to creatures that are increasingly unlike humans—from primates to earthworms—we are increasingly unjustified in ascribing a mental life to those animals. Now an organism either does or does not have a conscious life; for example, a worm either does or does not feel pain. But we have more grounds for ascribing painful sensations to primates than to worms according to the methodology above. All living animals have souls if they have organic life, regardless of the degree to which they are conscious, but we are justified in attributing less and less to the animal soul as the animal in question bears a weaker analogy to us.
In light of this methodology, what can we say about animal souls? Obviously, our answer will vary depending on the animal in question. But it seems reasonable to say that virtually all animals have certain sorts of sensations, for example, experiences of taste and pain. Many if not most animals seem to have desires as well, such as a desire for food. Many animals appear to engage in thinking and have certain sorts of beliefs. For example, a dog seems to be able to engage in means-to-ends reasoning. If he wants to go through a specific door to get food, and if the door is closed, he can select an alternative means to achieve the desired end. Many animals also engage in willings: that is, they will to do certain things, though there is no adequate evidence to suggest that they have libertarian freedom. It is more likely that an animal’s will is determined by its beliefs, desires, sensations, and bodily states.
There are several capacities that animals do not seem to have. We have already mentioned libertarian freedom of the will. Animals also do not seem to have moral awareness. Animals do not seem to grasp key notions central to morality such as the notion of a virtue, of a duty, of another thing having intrinsic value and rights, of universalizing a moral judgment, and so on. They cannot distinguish between what they desire most and what is most desirable intrinsically. Alleged altruistic behavior can be explained on the basis of animal desire without attributing a sense of awareness of intrinsic duty to the animal.
Animals, therefore, do not seem to be capable of having a conflict between desire and duty, though they can experience a conflict between desires (e.g., to scratch the chair and to avoid being spanked). Animals do not seem to be able to entertain various sorts of abstract thoughts, for example, thoughts about matter in general or about love in general or even about food in general. Moreover, animals do not seem to be able to distinguish between true universal judgments (all alligators are dangerous) and mere statistical generalizations (most alligators are dangerous) nor do they have a concept of truth itself.
While this is controversial and I may be wrong in this judgment, animals do not seem to possess language.17 One problem that keeps people from getting clear about this is the presence of certain ambiguities about what language is. More specifically, the question of animal language cannot be adequately discussed without drawing a distinction between a sign and a symbol. A sign is a sense-perceptible object, usually a shaped thing like the characters “BANANA” or a sound (the utterance of “BANANA”). Now if an animal (or a human infant for that matter) comes to experience repeatedly the simultaneous presence of a sign (the visual presentation of BANANA) and the presence of a real banana, a habitual association will be set up such that the animal will anticipate the sense perception of a real banana shortly after seeing this shape: BANANA. In the case of the animal, BANANA does not represent or mean a banana, so it is not a symbol. Rather, BANANA is merely a certain geometrically perceived shape that comes to be associated with a banana in such a way that the latter is anticipated when the former is observed.
By contrast, real language requires symbols and not mere signs. When language users use the word banana, it is used to represent, mean, and refer to actual bananas. Now the evidence suggests that animals have certain abilities to manipulate and behaviorally respond to signs, but it is far from clear that they have a concept of symbols. One reason for this claim is the lack in animals of grammatical creativity and logical thought about language itself that is present in real language users.
Finally, St. Augustine once noted that animals have desires, but they do not have desires to have desires. They may have beliefs, volitions, thoughts, and sensations, but they do not seem to have beliefs about their beliefs, they do not choose to work on their choices, they don’t think about their thinking, and they are not aware of their awarenesses. Nor do they seem to be aware of themselves as selves. In short, they do not seem to be able to transcend their own states and engage in reflection about their own selves and the states within them.
Animals are precious creatures of God and ought to be respected as such. But the animal soul is not as richly structured as the human soul, it does not bear the image of God, and it is far more dependent on the animal’s body and its sense organs than is the human soul.
In chapter 1, I claimed that the central issues involved in grasping the nature of consciousness and the soul are philosophical/theological and not scientific. Neuroscience is a wonderful tool for getting at the various causal interactions and dependency relations between brain and soul, but it is inept for resolving disputes about the nature and existence of consciousness and the soul. The central issues in those disputes include the philosophical, theological, and commonsense topics treated in chapters 2 through 4. Neuroscientific data are simply irrelevant for addressing those topics.
As a final illustration of the irrelevance of neuroscientific data for these topics, consider what we have learned about mirror neurons. These are neurons that respond during a motor activity and while an organism views another creature perform that same activity. For example, certain mirror neurons are activated in a chimpanzee’s brain when it reaches for food, and those same neurons are activated when the chimpanzee watches another animal reach for food. Scientists think that mirror neurons are the neurological bases for various conscious activities such as experiencing empathy, comprehending the actions of others, anticipating action, and imitating others.
Now what exactly does the discovery of mirror neurons show regarding the central issues of the mind/body problem? Very little. One could interpret these causal, dependency data (e.g., our ability to empathize is causally dependent on healthy, functioning mirror-neuronal activity) in at least three empirically equivalent ways (ways that are consistent with the same scientific data such that those data cannot count in favor of one view over the others): (1) the feeling of empathy is identical to the mirror-neuronal activity (reductive physicalism); (2) the feeling of empathy is an irreducible mental property that emerges on mirror-neuronal activity (mere property dualism); (3) the feeling of empathy is an irreducible mental property that occurs in the soul and whose presence is causally dependent on proper mirror-neuronal activity in the brain (substance dualism).
My view is (3), but in any case, deciding among these three is not a scientific activity. After all, is it really so surprising to discover that various mental functions are causally dependent on a working body and brain? The ancients knew nothing about the brain, but they knew that if your eye is poked out, you will not be able to see, or if you get hit in the head, you get dizzy. But they didn’t conclude from these facts that the eye sees or the brain has consciousness. The causal dependency of feelings of empathy on mirror-neuronal activity is no different in kind from the dependence of sensations of sight on the eyes. It’s just that today we have a more detailed story of the dependency, and that’s really the only difference between the ancients and us.
In his 1886 lectures on the limitations of scientific materialism, John Tyndall claimed that “The chasm between the two classes of phenomena” (mental and physical phenomena) is of such a nature that we might establish empirical association between them, but it would still remain intellectually impassable. Let the consciousness of love, for example, be associated with a right-handed spiral motion of the molecules in the brain, and the consciousness of hate with a left-handed spiral motion. We should then know when we love that the motion is in one direction, and when we hate that the motion is in the other; but the “WHY” would remain as unanswerable as before.18
In my view, not much has changed since Tyndall penned these remarks. The details have changed, but the central issues have not.
A Case for Substance Dualism and the Immaterial Nature of the Self
Our Basic Awareness of the Self
We are aware of our own self as being distinct from our bodies and from any particular mental experience we have, and as being an uncomposed, spatially unextended, simple center of consciousness. This grounds my properly basic belief that I am a simple center of consciousness. In virtue of the law of identity, we then know that we are not identical to our body, but to our soul.
Unity and the First-Person Perspective
If I were a physical object (a brain or body), then a third-person physical description would capture all the facts that are true of me. But a third-person physical description does not capture all the facts that are true of me. Therefore, I am not a physical object. Rather, I am a soul.
The unity of our conscious experience is best explained by an uncomposed mental substance, our soul.
The Modal Argument
I am possibly disembodied (I could survive without my brain or body); my brain or body are not possibly disembodied (they could not survive without being physical); therefore, I am not my brain or body, I am a soul.
Free Will, Morality, Responsibility, and Punishment
Property dualism and physicalism deny libertarian freedom. Property dualism attempts to explain human action either through epiphenomenalism or event-event causation. Yet, given the truth of a libertarian account of free will, moral ability, moral responsibility, and punishment, property dualism and physicalism are false. However, our commonsense notions about free will, moral ability, responsibility, and punishment, which are almost self-evident, are plausible given substance dualism.
Sameness of the Self Over Time
A physical object composed of parts cannot survive over time as the same object if it comes to have different parts. My body and brain are physical objects composed of parts that are constantly changing, and therefore cannot survive over time as the same object. However, I do survive over time as the same object. Therefore, I am not my body or my brain, but a soul.
The Human Soul
Five States of the Soul
Sensation: A state of awareness, a mode of consciousness, e.g., a conscious awareness of sound or pain.
Thought: A mental content that can be expressed in an entire sentence and that only exists while it is being thought.
Belief: A person’s view, accepted to varying degrees of strength, of how things really are.
Desire: A certain inclination to do, have, avoid, or experience certain things.
Act of will: A volition or choice, an exercise of power, an endeavoring to do a certain thing, usually for the sake of some purpose or end.
Faculties of the Soul
Sensory faculties: Sight, smell, touch, taste, and hearing.
The will: A faculty of the soul that contains my abilities to choose.
Emotional faculties: One’s abilities to experience fear, love, and so forth.
Mind: That faculty of the soul that contains thoughts and beliefs along with the relevant abilities to have them.
Spirit: That faculty of the soul through which the person relates to God.
Animal Souls
Animals have a soul, but it is not as richly structured as the human soul. It does not bear the image of God, and it is far more dependent on the animal’s body and its sense organs than is the human soul.
Final Reflection about the Relevance of Neuroscientific Data
Neuroscience is a wonderful tool, but it is inept for resolving disputes about the nature and existence of consciousness and the soul. The central issues in those disputes include philosophical, theological, and commonsense topics. Neuroscientific data are simply irrelevant for addressing those topics.
Act of will: A volition or choice, an exercise of power, an endeavoring to do a certain thing, usually for the sake of some purpose or end.
Belief: A person’s view, accepted to varying degrees of strength, of how things really are.
Cartesian dualism: The mind is a substance with the ultimate capacities for consciousness, and it is connected to its body by way of a causal relation.
Desire: A certain inclination to do, have, avoid, or experience certain things.
Emergent dualism: a substantial, spatially extended, immaterial self emerges from the functioning of the brain and nervous system, but once it emerges, it exercises its own causal powers and continues to be sustained by God after death.
Epiphenomenalism: The mind is a by-product of the brain, which causes nothing; the mind merely “rides” on top of the events in the brain.
Event-event causation: The first event, combined with the laws of nature, are sufficient to determine or fix the chances for the occurrence of the second event.
First-person point of view: The vantage point that I use to describe the world from my own perspective.
Faculty of the soul: A “compartment” of the soul that contains a natural family of related capacities.
Mind: That faculty of the soul that contains thoughts and beliefs along with the relevant abilities to have them.
Properly basic belief: A belief that is not inferred from any other belief(s), but is rationally justified by experience (by perception, for example).
Spirit: That faculty of the soul through which the person relates to God.
Thomistic substance dualism: The (human) soul diffuses, informs (gives form to), unifies, animates, and makes human the body. The body is not a physical substance, but rather, an ensouled physical structure such that if it loses the soul, it is no longer a human body in a strict, philosophical sense.
Thought: A mental content that can be expressed in an entire sentence and that only exists while it is being thought.
1. See Richard Swinburne, The Evolution of the Soul, rev. ed. (Oxford: Clarendon, 1997); Mind, Brain & Free Will (Oxford: Oxford University Press, 2013).
2. See J. P. Moreland and Scott Rae, Body & Soul: Human Nature & the Crisis in Ethics (Downers Grove, IL: IVP, 2000), chapter 6.
3. See William Hasker, The Emergent Self (Ithaca, NY: Cornell University Press, 1999).
4. Stewart Goetz, “Modal Dualism: A Critique,” in Soul, Body and Survival, ed. Kevin Corcoran (Ithaca, NY: Cornell University Press, 2001), 89.
5. For more on the unity of consciousness, the binding problem, and split-brain phenomena, see Tim Bayne, “The Unity of Consciousness and the Split-Brain Syndrome,” The Journal of Philosophy 105(6) (2008): 277–300; Tim Bayne and David Chalmers, “What Is the Unity of Consciousness?” in The Unity of Consciousness, ed. Axel Cleeremans (Oxford: Oxford University Press, 2003), 23–58. For an empirical argument against physicalism that centers on some of these considerations, see Eric LaRock, “An Empirical Case against Central State Materialism,” Philosophia Christi 14(2) (2012): 409–26.
6. Hasker, The Emergent Self, 122–46.
7. Cf. Keith Yandell, “A Defense of Dualism,” Faith and Philosophy 12 (1995): 548–66; Charles Taliaferro, “Animals, Brains, and Spirits,” Faith and Philosophy 12 (1995): 567–81.
8. In normal life, I may be focusing on speaking kindly and be unaware that I am scowling. In extreme cases (multiple personalities and split brains), I may be fragmented in my functioning or incapable of consciously and simultaneously attending to all of my mental states, but the various personalities and mental states are still all mine.
9. For two reasons, quantum indeterminacy is irrelevant here: (1) The best interpretation of quantum indeterminacy may be epistemological and not ontological. (2) If quantum indeterminacy is real, events still have their chances fixed by antecedent conditions, and this is inconsistent with agent causation since on this view nothing fixes the chances of a free action.
10. Timothy O’Connor has argued that agent causal power could be an emergent property over a physical aggregate. See his Persons and Causes: The Metaphysics of Free Will (New York: Oxford University Press, 2000). Subsequently, O’Connor has changed his view and opted for the idea that the agent is an emergent individual. See Timothy O’Connor and Jonathan D. Jacobs, “Emergent Individuals,” The Philosophical Quarterly 53 (2003): 540–55. For a critique of O’Connor, see J. P. Moreland, Consciousness and the Existence of God (London: Routledge, 2008), chapter 4.
11. For more on problems of material composition, see Michael Rea, ed., Material Constitution: A Reader (Lanham, MD: Rowman & Littlefield, 1996); Christopher M. Brown, Thomas Aquinas and the Ship of Theseus (London: Continuum, 2005).
12. The view I am advancing is called mereological essentialism (from the Greek word meros that means “part”). Mereological essentialism is the idea that an object’s parts are essential to its identity such that it could not sustain its identity to itself if it had alternative parts. Animalists and constitutionalists deny mereological essentialism. For a brief exposition of these views, see Eric Olson, What Are We? A Study in Personal Ontology (Oxford: Oxford University Press, 2007), chapters 2 and 3. In different ways, each view claims that, under certain circumstances, when parts come together to form a whole, as a primitive fact, the whole itself just is the sort of thing that can survive part alteration. In my view, this is just an assertion. The whole just is parts and various relations, and neither the parts nor the relations can sustain identity if alternatives are present. The whole is not a basic object—it is identical to its parts and relations.
13. Some claim that what unites all of one’s various psychological stages into the life of one single individual is that the stages stand in an immanent causal relation to each other. But an immanent causal relation is one that holds between two states in the same thing. Thus, before a causal relation can be considered an immanent one, there must already be the same thing that has the two states. Because the immanent causal relation presupposes sameness of the thing in question, it cannot constitute what it is for the thing to be the same. Further, the immanent causal view confuses what it is that causes an object to endure over time with what it is for the object to remain the same.
14. For an additional argument for substance dualism, see Peter Unger, “The Mental Problems of the Many,” in Oxford Studies in Metaphysics I, ed. Dean Zimmerman (Oxford: Clarendon Press, 2004), 195–222.
15. Biblical anthropological terms (heart, soul, spirit, mind) have a wide range of different meanings, and no specific use of a biblical term should be read into every occasion of the term. I am focusing here on a narrower, specific use of the term “spirit.”
16. For more on this, see Richard Swinburne, The Evolution of the Soul, rev. ed. (Oxford: Clarendon Press, 1997), 11–16, 180–96, 200–219.
17. Cf. Swinburne, The Evolution of the Soul, 203–19; J. P. Moreland, ed., The Creation Hypothesis (Downers Grove, IL: IVP, 1994), chapter 7.
18. John Tyndall, “Scientific Materialism,” in his Fragments of Science Vol. II (New York: P. F. Collier & Son, 1900), 95.