Can There Be Mind Over Matter?

By Susan J. Fleck. November, 2001.

I have a prodigious quantity of mind; it takes me as much as a week sometimes to make it up. – Mark Twain.

The mind does not create what it perceives, any more than the eye creates the rose. – Ralph Waldo Emerson.

The mind is like the stomach. It is not how much you put into it that counts, but how much it digests. – Albert Jay Nock.

One machine can do the work of fifty ordinary men. No machine can do the work of one extraordinary man. – Elbert Hubbard.

Imagination disposes of everything, it creates beauty, justice, and happiness, which are everything in this world. – Blaise Pascal.

What is a Human Mind?

What do we mean when we talk about the human mind? The first three definitions of “mind” in my dictionary suggest that we commonly think that the mind is not simply synonymous with the brain, although the second definition comes close to that premise: (1) The human consciousness that originates in the brain and is manifested especially in thought, perception, feeling, will, memory, or imagination; (2) The totality of conscious and unconscious processes of the brain and central nervous system that directs the mental and physical behavior of a sentient organism; (3) The principle of intelligence; the spirit of consciousness regarded as an aspect of reality: mind over matter (American Heritage). If we say “she has a mind of her own,” does this mean something further than saying “she has a brain of her own”?

This paper will defend the proposition that the mind is a ‘further fact.” By further fact I mean something in addition to the physio-chemical processes in the brain. A further fact also means something in addition to psychological continuity in comprising the essence of personal identity. While expanding on the concept of what a further fact is, I intend to show that holding this view does not violate Occam’s razor in a causal explanation of human activity such as thinking. Also, holding this view does not necessarily support a dual nature view of the universe: one of matter and spirit. Finally, this view does not support the dichotomy of mind and body. I will defend my proposition by guiding the reader through ideas expressed in most of the papers presented in the “Mind and Body” section of our Burr and Goldinger text (402-462). We will briefly review some tenets of materialism, interactionism, idealism, and Objectivism. Next, we will look at one instance of personal identity: that it is bound by the concept of surviving. Lastly, there will be a short discussion contrasting the nature of computers with that of human thinking. By exposing the weaknesses and strengths in these authors’ arguments, I intend to weave them together into a common theme to support the idea that the mind is a further fact.

Materialism

Hugh Elliot describes the three main principles which defend the doctrine of materialism: (1) The uniformity of law; (2) The denial of teleology (purpose); and (3) Monism, i.e.: “The denial of any form of existence other than those envisaged by physics and chemistry [. . .]” (403). The third principle may be restated to say that everything that exists has some kinds of material characteristics and qualities.

For Elliot, every event in the Universe, including things like human thinking, daydreaming, imagining, intending, “are expressible purely in terms of matter and motion.” (Note: he admits that science can not yet describe and explain how this works in our brains, but ex hypothesi this must be so.) I suppose that Elliot is thinking of either the Big Bang theory or a never-ending Expanding and Contracting Universe theory when he states: “The existing Universe and all things and events therein may be theoretically expressed in terms of matter and energy, undergoing continuous redistribution in accordance with the ordinary laws of physics and chemistry.” He claims that men of science have long believed that all manifestations within our experience can be attributed to these laws. Moreover, he avers that it would be a violation of William of Occam’s razor to introduce either consciousness or mind as a separate entity—that would be superfluous in determining an explanation of mental processes. (404)

Is there not something special about feeling the sublime in a beautiful sunset? Is there not something special about you being you and me being me? Are the experienced sunset, and you, and I, and everything we think, say, and do, all determined by matter and energy that all started awhirl eons ago? Can there be no purpose to our actions? If so, why bother with anything? Are these questions merely the musings—the anxieties and heartbreak of existentialists? Was it really determined that I would interject these questions at this time, or, rather, could I have freely chosen other words, or omitted this paragraph entirely?

Purposive, Voluntary Actions

Regarding purposive and voluntary actions, Elliott states:

They belong to the category in which the immediate stimulus is in the brain itself, and is to be regarded as consisting of rearrangements of the matter and energy contained in the nervous substance of the brain. The brain during consciousness can never be still, and its unceasing activities supply the stimulus, not only for purposive, but for all actions of an intellectual character. Now this permanent cerebral activity can be divided into a number of different types, known psychologically by such names as memory, imagination, reason, etc. Although nervous physiology has not yet advanced far enough to enable us to say what are the different kinds of material processes in the brain corresponding to these psychical processes, yet there is no doubt that the psychical distinction is based upon some actual distinction in the corresponding activities occurring in the brain. (406-7)

Elliot’s argument to dismiss purposiveness, especially in individual human activity, is weak. Although it may be true that the brain can never be still during consciousness, this by itself does not explain away purposiveness: it is not philosophically significant. Elliot admits that we are as yet unable to define material-energy processes in the brain corresponding with different types of mental activity. It seems that he is trying to make a truth claim where one is not yet proved: an appearance of purposive activity is merely the result of brain-energy with an antecedent physical-energy cause. Lest we derive pleasure from any purposive activity we have engaged in, let us be reminded of Elliot’s conclusion: “By this name [purposive] we designate the majority of those redistributions which issue from the little whirlpools of matter and energy called organisms, and those factors in particular by which the immediate continuance of such whirlpools is ensured” (407).

Elliot provides this example: “You move your arm by an act of will, or what seems to be a non- material cause, and yet it is conclusively established that the movement of the arm is due to definite material changes occurring in the brain, and caused by the fixed laws of physics and chemistry in the most determinist fashion” (409). He has explicitly stated that strict materialism, as he describes, entails strict determinism. It is noteworthy that his view of materialism reduces everything to the laws of physics and chemistry, but leaves no room for differences in biology—the science of living things. Let us agree that the actual movement of the arm can be explained by purely material, physical and chemical forces in the brain and body. This still does not explain the ‘willing’ of the arm to move; the thought that produced the desire for some future outcome.

Epiphenomenalism

Some philosophers posit a separate entity, a mind, as the explanation for our various mental “events.” Elliot is sure that he has convinced us that the only plausible hypothesis for a mind separate from the brain itself is that of epiphenomenalism. According to the Cambridge Dictionary of Philosophy, epiphenomenalism “is the doctrine that physical states cause mental states, but mental states do not cause anything. [. . .] there is only one-way psychophysical action—from the physical to the mental” (598). One would have to agree with Elliot that this view of the mind does not provide us with a reason to believe in a separate mind entity, since this kind of entity can not provide any cause of action, purpose or any sense of agency. However, I am not convinced that epiphenomenalism is the only theory of mind to be considered: he would be correct only if one accepts all of the preceding premises in his argument.

Furthermore, Elliot has painted with too broad of a stroke to simply brush off all non-material entities if he can prove that there is no non-material mind: “[. . .] for if mind can be identified with matter, all other kinds of non-material entities must lapse, even those described by religious systems . . .” (408). One can certainly speculate that there is a Prime Mover, say, in the Aristotelian sense, from which all matter and energy and universal laws came. If such a Being exists, then It existed before the possibility of any human mind existed. By sweeping away the human mind, one does not necessarily account for the non-existence of all non-material entities. Materialists and scientists must all agree that there is no where to turn to for proof for or against a God who may have created all of this matter and energy; or, if the Universe is simply eternal without a Creator or a beginning, then, how to prove that.

Evolutionary Consideration

Elliot gives us another false either/or possibility to explain away the mind. Given that we accept the general processes by which all things living and non-living evolved over time, he claims that in order to accept the proposition of minds separate from brains, we must therefore believe one of only two possibilities: “either that inorganic matter has a psychical accompaniment, or else that, in the course of evolution, there was a sudden leap: mind was suddenly intruded at some period of Man’s past history” (410). I propose a third possibility: mind, per se, as with most of our advanced biological human systems, did not suddenly appear in the course of evolution. Rather, it was developed through various emergent biological properties over a long course of evolutionary time.

Determinism Rejected

Cyril Joad is one author who finds materialism to be an unsatisfactory explanation of psychology and biology. He thinks that in human beings there is “this principle of life [that] expresses itself at the level of what is called mind, that this mind is distinct from both body and brain, and, so far from being a mere register of bodily occurrences, is able, acting on its own volition, to produce such occurrences [. . .]” (411). I think Elliot’s weakest argument is in refuting purposive thinking and resulting behavior. It seems that one can only accept materialism if one accepts strict determinism. In that case, there is no free will. But Joad does not accept this account: “]. . .] the capacity to be influenced by events which lie in the future seems inexplicable on the stimulus-response basis; the thought of what does not exist may be allowed to influence the mind, but it is difficult to see how the non-existent can stimulate the body . . . .” (413).

Apprehending Meaning

Joad presents a strong argument for a mind that apprehends and comprehends meaning as opposed to mere stimuli of marks on a paper (words and sentences), or sounds of someone speaking. Meaning, per se, is immaterial and can be grasped only by a mind. Similarly, only a mind can synthesize isolated sensations, say from various musical instruments, and apprehend and appreciate the whole of a symphony. Although the brain may be stimulated and it may be producing physical responses, only an individual mind can perceive the sum of the parts. “This faculty of combining or putting together seems to involve the existence not only of a mind,” Joad exclaims, “but of a mind of an active, creative type which is able to go out beyond the raw material afforded by our bodily sensations, and to apprehend ideal objects as wholes [. . .]” (415).

If the mind is an active, dynamic, synthesizing, and creative force, as Joad claims, how does he deal with the problem of the relationship of the mind to the brain? After all, this is THE problem philosophers have been trying to solve ever since Descartes sliced us into separate minds and bodies. I like the analogy of a play that Joad provides to describe this concept:

If you were to observe a man’s brain you would know just as much of his thoughts as found vent in gestures. You would know, in other words, all that his thoughts imply in the way of actions or the beginnings of actions, but the thoughts themselves would escape you just as the words and meaning of the play would escape the deaf spectator. This is what is meant by saying that the mind overflows the brain. (416)

Primacy of Consciousness View

We have discussed Elliot’s material-only universe; Joad’s mind-material interactive universe; now we move on to examine Arthur Luce’s mind-only universe.

Luce is clearly carrying on George Berkeley’s “primacy of consciousness” view of the universe as opposed to a “primacy of existence” view. Without naming Plato, Kant, or Berkeley in his paper “Sense Without Matter,” these philosophers are lurking between the lines. He does discuss Aristotle’s theory of sense-perception explicitly. Luce is arguing from false dichotomies in support of the idea that there is no such thing as matter.

An extremely short review of this topic may shed light on Luce’s argument. With Aristotle’s theory, when we perceive some existent thing, there is both the sense-data that we actually perceive and the material substance that is itself unperceived and unperceivable. With Plato, things we perceive are not real; they are merely copies of the real ideal of whatever it is (table, lamp, etc.): the “real” thing is located in the “real” world, while we live only in the unreal world of shadows. With Kant, what we perceive is not the “thing in itself,” but our perceptions are the product of whatever categories our pre-wired brain has imposed upon the “thing in itself.” Berkeley responded to Locke, who inherited from Galileo, Descartes, Newton and Boyle a distinction between primary and secondary qualities. As Jonathan Bennett describes, Locke puts the objective world, the world of real things beyond our reach “on the other side of the veil of perception” (69). Primary qualities that a thing would keep through any changes, qualities that are real and physical for Locke and Boyle, have to do with size, shape, motion or rest. Secondary qualities are color, temperature, smell, taste and sound (Tipton 30).

Berkeley often stated that the root of all skepticism is the belief in mind-independent material substance (Bennett 71). Berkeley attempted to cure the world of its skepticism:

That the qualities we perceive are not on the objects: that we must not believe our senses: that we know nothing of the real nature of things, and can never be assured even of their existence: that real colours and sounds are nothing but certain unknown figures and motions: [. . .] these are the strange notions which [. . .] embarrass the mind with endless doubts and difficulties. And it is against these [. . .] I endeavor to vindicate common sense. (287)

Berkeley repeatedly explains that sensible things or objects are those which can be perceived, and that nothing can be perceived except ideas. His famous conclusion is that No object can exist unless it is perceived by someone. Since things are statements about ideas, "Qualities, as hath been shewn, are nothing else but sensations or ideas, which exist only in a mind perceiving them" (Qtd. in Bennett 73). Berkeley was sure that any arguments which could demonstrate that secondary qualities, e.g. colors and tastes, exist only in the mind, then those same arguments would apply to so-called primary qualities - extension, figure, and motion.

Rejecting Matter

Luce is carrying on Berkeley’s project in denouncing a theory that requires a dual aspect of nature: qualities which we sense and the unperceivable things in themselves. However, instead of giving up a false dichotomy, Luce is rejecting the concept of matter altogether. Luce asks why he should believe in the matter of materialism: “[. . .] set aside the prejudice that would identify with matter the chemical atom, or the subatomic objects of nuclear physics; set aside the legend of the constant sum-total of energy from which all springs and to which all returns [. . . .]” By sweeping aside the very scientific foundations for a theory of matter, he then complains that philosophers “never attempt to prove its existence directly” (420). One can easily win an argument if one brushes aside all of the credible evidence for the opposing viewpoint. Since Luce is arguing from the false dichotomy that materialism rests upon things-in-themselves being separate from their sense-data, he can conclude ex hypothesi that matter does not support sense-data, and therefore, matter is superfluous to a causal explanation of what we are sensing (420). Luce does acknowledge that modern science has attempted to identify matter in terms of “atomic energy or with the rapid movement of the tiny parts and particles of elements,” but he views these only as current-day theories, rivaling older causal theories of matter, but that they are of no consequence for explaining a causal connection between matter and senses.

Objectivism

We have reviewed the materialist, “all-is-matter,” and the opposing idealist, “all-is-ideas,” viewpoints. Let us now turn to Ayn Rand’s Objectivism to learn how her “object-as-perceived” interactionist position supplements Joad’s approach, and how it gets rid of the “in the object” or “in the mind” either/or dichotomy. I will only summarize a few points from this philosophy that address the subjects of matter and human sensing.

As far as discovering the fundamental attributes of matter, there is no philosophical method, but rather only scientists' methods of specialized observation, experimentation, and inductive inference. Whatever such attributes turn out to be, they have no philosophical significance - not to metaphysics and not to epistemology (Peikoff 44). Rand posits that scientists do discover the ultimate ingredients of the universe - call them 'puffs of meta-energy'. The three dimensional material world that we perceive, it is found out, is not a primary, but merely an effect of these puffs acting on men’s' means of perceptions (which are also made up of these puffs). What does this prove philosophically? Nothing, because even though the things we perceive would not be primaries, they would nevertheless be unimpeachably real. We cannot condemn something as unreal on the grounds that it is 'only an effect', which can be given a causal explanation. "One does not subvert the reality of something by explaining it. One does not make objects or qualities subjective by identifying the causes that underlie them” (Qtd. in Peikoff 45).

Skeptics who condemn human knowledge as invalid because it rests on sensory data imply that knowledge should have depended on a 'direct', non-sensory illumination. "Are they saying, ‘If I had created reality, I would have chosen a different cause for knowledge.'?" Knowledge does rest on sensory data in the real world (Qtd. in Peikoff 27). At the human level, sensory perception is conceptual in nature. It is not automatic or infallible. It can err, distort, and depart from reality (through ignorance or evasion). Man, therefore, must learn how to use his mind to distinguish truth from falsehood and how to validate our conclusions. We start off with a tabula rasa, a blank tablet, and all of our conceptual content is derived from the evidence of the senses. If senses are not valid and do not provide a knowledge of reality, then the resultant concepts are nonsensical, and the whole cognitive process is terminated (Peikoff 38).

Perceiving Attributes of Entities

Entities constitute the content of the world men perceive. We observe (some of) their attributes. The byproduct of the process of conceptual identification is the philosophers' inventory of categories of being: qualities (red, hard); quantities (five inches, six pounds); relationships (to the right of); actions (walking). None of these categories, Rand claims, has metaphysical primacy; none has any independent existence; all represent merely aspects of entities (Peikoff 13). There are two dominant positions regarding qualities: "in the object" or "in the mind". There is another alternative where a quality is derived from an interaction between external objects and man's perceptual apparatus. It is not 'in the mind' apart from the object; it is man's form of grasping the object. Nor is it 'in the object' apart from man (or other perceiving creature); it is man's form of grasping the object. It is the product of an interaction between two entities, object and apparatus, and cannot be identified exclusively with either. This third alternative is "object-as-perceived” (Peikoff 46).

Those condemning the senses as deceptive because sense qualities are merely effects seem to be saying "I demand that the senses give me not effects, but irreducible primaries." Perception is a necessary process of interaction and knowledge: there is no way to perceive an object that does not somehow impinge on one's body. Therefore, sense qualities must be effects. "To reject the senses for this reason is to reject them for existing” (Qtd. in Peikoff 47).

Anti-skepticism

Of course, erkeley would be horrified about this line of thinking and the whole system of Objectivism, which is as anti-religious as it is anti-idealist, anti-materialist, and a whole lot of other 'antis'. But Objectivism has one goal in common with Berkeley, and that is anti-skepticism. It just solves the problem in a radically different way:

. . . Objectivists reject the key skeptic claim: that man perceives not reality, but only its effects on his cognitive faculty. Man perceives reality directly, not some kind of effects different from it. He perceives reality by means of its effects on his organs of perception. Nor can one reply that man's perception of reality, since it is mediated by the senses, in only "indirect." What then would "direct perception" denote? It would have to denote a grasp of reality attained without benefit of any means. (Peikoff 51)

Survival Criterion

Before we make up our “minds” about “minds,” let us look at an additional aspect, one of personal identity that Derek Parfit brings to this discussion. Godfrey Vesey, in his dialogue with Parfit, summarizes the common belief about personal identity as this: “whatever happens between now and some future time either I shall still exist or I shan’t. And any future experience will either be my experience or it won’t. In other words, personal identity is an all or nothing matter: either I survive or I don’t” (435). Parfit claims that this view is false because we can imagine several cases where we can not answer the question, “Will the future person be me—or someone else” (435)? He argues that personal identity is bound up in psychological continuity and there is no further fact in our identity. Since there could be cases, in the future, where there are two or more persons with the same psychological continuity, as say, in the case where one’s brain is split in two and each half is put in others’ bodies, then we must give up the all-or-nothing belief in personal identity. We must then realize that psychological continuity, and our possible survival, is a matter of degree (440).

Tis viewpoint has enormous impact for ethics. For example, because one undergoes radical [psychological] change over time, one should be less liable for crimes committed in the distant past, compared to crimes committed in the recent past (Parfit 440). Another implication is that, with possible branching into two or more people, we should recognize our psychological connections with all persons past and in the future. Therefore, because of this closer relationship, we must hold altruism in the highest regard as a principle of living in relationship with other persons.

The weakness in Parfit’s argument is that highly dubious science fiction is necessary in all of his cases he uses to knock down the common notion of personal identity. He is subverting the law of identity with regard to what a human being is, in describing what a human being might be in some futuristic possible world. Even though it is cited that there was a successful transplant of one monkey’s head on to another monkey’s body, it is a long stretch of the imagination to imply that one could divide a person’s brain in two and have complete psychological continuity in two resulting persons. In cases where Parfit describes replicating brain cells and subsequent gradual replacement, or duplication, of such cells, he is assuming that there is no further fact of a mind-in-a-brain, and that such replication/duplication is possible. He has thus created a false, circular argument. We should give no moral force to such science fiction until such time that cognitive-neural science can substantiate such claims—if it is possible to do so.

Can Computers Think?

I may be more easily persuaded to give up the notion of a further fact in order to explain a mind as something more complex than a reduction to materialism, if I were led to believe that computer-machines can really think. By “think,” I mean in virtually all respects that humans think. Christopher Evans provides us with his solutions to most arguments and objections to the idea that machines can, or ever could, think (442-454). Although Evans counters them to some degree, three of the objections that he cites are strong arguments against the notion that computers can think. Let us briefly examine these.

(1) “The Personal Consciousness Objection” claims that, for example, machines can not create and write concertos on their own, and, furthermore, if they could, they would not feel the pleasure of their successes, nor could they know that they had written them (Evans 445). This claim is hard to prove or disprove for the same reason that John Hospers explains in his paper “The Problem of Other Minds:” I can not feel someone else’s pleasure, and I can not know someone else’s pleasure (427-433). We would only have the machine’s “reporting” to judge whether or not it passes this test. One could at least design a credible set of questions to pose, a.k.a. “a Turing Test” (Evans 445-6), to form an opinion about the level of thinking ability—that is, after the machine advanced to a stage where it could create concertos.

(2) The “It Is Not Biological Objection” supposes that our human, biological central nervous system may be more than having basic “on/off” units of communication. Therefore, computers, being digital in nature, may become extremely intelligent (have a vast data base of knowledge), but they would never be able to think. Evans acknowledges that there is not enough evidence, or knowledge, about how humans think at this time to refute this objection, even though, he claims, “there is no shred of evidence to suppose that only non-digital systems can think” (447).

(3) The “It Can Not Be Creative Objection:” Evans proposes that to overcome this objection, a computer must demonstrate “a skill which has never been demonstrated before and which was not specifically taught to [it] by someone else, or in the intellectual domain provides an entirely novel solution to a problem [. . .]” He claims that this has been accomplished and he gives two examples—when a computer solved the “four color problem,” and when a computer generated a totally new proof in geometry (450-1). Although these examples clearly demonstrate creativity as Evans has defined creativity, I would want to tag the concept of “purposiveness” onto “creativity,” for a more comprehensive notion of a machine’s ability to think. One can imagine such a computer as “HAL,” in “2001: A Space Odyssey,” to envision a machine with [evil] intentions. (It is interesting to note that the letters “HAL” are the ones before the letters “IBM.”) Well, 2001 has almost come and gone, and HAL is no where to be seen or heard from—yet!

Evans admits as much when he states: “[. . .] computers have quite a way to go before they jump the hurdle so cleverly laid out for them by Turning [in order to pass the “thinking” test].” However, Evans claims that he has presented a compelling case for us to believe “[. . .] that the difference, in intellectual terms, between a human being and a computer is one of degree and not of kind” (454). I disagree. The kind of difference lies in the fact that humans are living, biological beings, with minds comprised of a further fact: minds that have evolved, over long periods of time, with such emergent properties to give us the ability to think, feel, imagine, intend, and create. I agree with Jenny Teichman who maintains “there are good reasons for believing that a correct analysis of human thinking has to mention human life.” She knows the danger of reducing human thinking to resemble the processes of sophisticated machines: this leads one to ask, if human thinking is like that of a machine, then what is so [philosophically/ethically] important about living things? Why should we then have respect for human life (455-6)?

Language

In order for humans to think, they must use language. Computers deal with codes and languages. But, as Teichman points out, “it is commonly said that [computers] do not really think because they have syntax without semantics. [. . .] that computers use linguistic rules but don’t know the meanings, the contents, of the strings of symbols which the [programmed] rules generate.” Computers do not have the ability, like humans do, for abstraction, for making connections between words and things in the world that the words refer to. Humans take in, via the senses, the physical inputs of, e.g., photons and sound waves, which are purely physical phenomena. Through the process of abstraction and differentiation, we learn how these sense inputs represent the world outside of our minds. With computers, all inputs (programs, facts, etc.) have been given content by humans: “The semantic function, the content, enters the system indirectly, via the human designer” (458).

In addition to merely processing information, Wittgenstein reminds us that human thinking “is a collection of processes, states, and dispositions such as hoping, day-dreaming, imagining, predicting, concentration, worry, fear, belief and expectation” (Teichman 459). I agree with Teichman:

The significance of this is that only a holistic theory which allows for connections between the varieties of thought can give an adequate account of human (paradigm) thinking. [. . .] although machine-states have electrical connections (of course), these could not mimic the links between human beliefs and desires and emotions because machines don’t have any desires and emotions in the first place. (460-1)

Conclusion

The all-is-matter and all-is-ideas view of the world is not tenable for reasons argued above. Teichman points out: “Reductive theories, whether ontological, epistemological or ethical, often turn out to be inadequate. The unwise use of Occam’s Razor cuts off too much” (455). Parfit has not presented a compelling reason to give up the notion of a further fact in our identity. While it might be claimed that machines can think, in so far as they meet a “Turing’s test,” there are aspects of human minds that machines will not be able to duplicate. For now, I will adopt the world view as discussed by Rand, Joad, and Teichman: that there is interaction between my mind and the outer world of existence. Their arguments support the notion of a further fact of a mind without imposing a dualistic structure on the universe, and without hanging onto a false dichotomy of mind and body. One can still hold the opinion that the mind is the brain (and no more), while still recognizing that the brain is the product of eons of evolutionary processes: the brain is of the biological, living world, and it now possesses amazing properties (a further fact over and above merely physical-chemical processes) that have emerged to give us the ability to think, create, and be individual humans—individuals that cannot be divided, or branched because of the very nature of what it means to be a human.

*****

Works Cited

Audi, Robert, ed. The Cambridge Dictionary of Philosophy. Cambridge: Cambridge University Press, 1995.

Bennett, Jonathan. Locke, Berkeley, Hume: Central Themes. Oxford: Clarendon Press, 1971.

Berkeley, George. “Three dialogues Between Hylas and Philonous, in Opposition to Sceptics and Atheists.” The Empiricists: Locke, Berkeley, Hume. New York: Doubleday. Anchor Books Edition, 1974.

Burr, John R., and Milton Goldinger, eds. Philosophy and Contemporary Issues. 8^th ed. Upper Saddle River: Prentice Hall, 2000.

Elliot, Hugh. “Materialism.” Burr and Goldinger. 402-410.

“epiphenominalism.” Def. The Cambridge Dictionary of Philosophy. Ed. Robert Audi. Cambridge: Cambridge University Press, 1995.

Evans, Christopher. “Can a Machine Think?” Burr and Goldinger. 442-454.

Hospers, John. “The Problem of Other Minds.” Burr and Goldinger. 427-433.

Joad, C. E. M. “The Mind as Distinct from the Body.” Burr and Goldinger. 411-416.

Luce, A. A. “Sense Without Matter.” Burr and Goldinger. 417-426.

“mind.” Def. Noun. The American Heritage Dictionary. Release 1.1 (software). Houghton Mifflin Co. 1992. Writing Tools Inc. 1992.

Parfit, Derek and Godfrey Vesey. “Brain Transplants and Personal Identity: A Dialogue.” Burr and Goldinger. 434-441.

Peikoff, Leonard. Objectivism: The Philosophy of Ayn Rand. New York: Penguin Books, 1991. Note: The section describing Ayn Rand’s philosophy in this essay, was copied from a previous paper I wrote in November, 1993, titled: “Berkeley – on Qualities.” (Also published on www.susanfleck.com website.)

Teichman, Jenny. “Human Beings and Machines.” Burr and Goldinger. 455-462.

Tipton, I.C. Berkeley: The Philosophy of Immaterialism. London: Methuen & Co. Ltd., 1974.