Maverick Philosopher

Mental states such as wanting, imagining, perceiving, etc. exhibit intentionality, and they do so by their very nature: they are essentially (not accidentally) of or about or directed to objects. I cannot want without wanting something, a dog for instance. What I want may or may not exist without prejudice to my wanting it. My wanting a three-headed dog does not entail the existence of a three-headed dog. And the nonexistence of such a dog leaves my thought untouched: My thought is what it is, and has the content it has, despite the nonexistence of three-headed dogs. Compare wanting to owning: if I own a three-headed dog, then there exists a three-headed dog. So if there are no three-headed dogs, then I cannot own one. Ownership is held hostage to the existence of things owned.

Owning is a relation: the nonexistence of one its terms (relata) entails the relation's nonobtaining. Wanting is not a relation -- though it is relation-like, ein Relativliches, as Brentano observed in 1874 -- since the nonexistence of the thing wanted leaves the wanting unaffected. The same goes for all cases of intentionality. None of them are relations strictly speaking.

Now compare wanting a dog, a beer, a ham sandwich, a matter transmitter. What Searle calls the "psychological mode" is the same in all four cases: all four intentional states are tokens of the type, wanting. But the intentional contents are different.

One question is this: In virtue of what does an intentional state possess content? A related question: In virtue of what does an intentional state possess the specific content that individuates it? For Fodor a state gets its content from external relations to the world. Things in the external world cause our intentional states to have the content they have.

Although it is entirely 'natural' for a naturalist to say something like this, the suggestion is fraught with difficulties.

1. First of all, some thoughts are about the nonexistent. But what does not exist cannot cause anything. So it cannot be the case that all thoughts derive their content from things in the external world. Since Cerberus does not exist, he cannot be causally responsible for my Cerberus-thoughts. The thought has the content it has despite the fact that nothing answering to it exists in the external world.

2. But even in the case of thoughts about existent items, causal relations cannot suffice to explain content. Suppose I am thinking about my cat Caissa. What makes this cat thought about Caissa? The idea is that there is a causal chain, commencing with Caissa, that terminates in my having the thought in question. But this is hopeless for reasons spelled out in a previous post. Briefly, all sorts of things in the external world are involved in the etiology of my thought; but my thought is precisely about Caissa. And as Putnam has argued, any attempt at specifying the salient cause, the cause that brings about the cat thought, will presuppose intentional notions.

3. Suppose I am thinking about Hal, who exists, but I attribute to him a property he does not possess. The content of my thought is: Hal is hypertensive, when in truth he is hypotensive. Since hypertensive Hal does not exist, how can he cause my false thought about him to have the content it has?

Naturalists have answers to these sorts of objections. My claim, however, will be that their answers just make things worse.

Now if propositions are the primary truth-bearers, then propositions, though distinct from the declarative sentences used to express them, must possess an internal structuration isomorphic to that of a declarative sentence. Alan Rhoda questioned this in a comment, citing Robert C. Stalnaker. According to Stalnaker (Inquiry, MIT Press, 1984, p. 3), "propositions lack structure of the kind that reflects the semantic structure of the sentences that express them." So we need to examine Stalnaker's theory of propositions.

1. We can introduce the notion of a proposition by saying that propositions are the vehicles or bearers of the truth-values. We can also say that they are the objects (accusatives) of such propositional attitudes as belief and desire. So far, agreement reigns. But to say the foregoing is just to say that propositions are entities that play a certain role, the role of truth-bearer, and the role of objects of the attitudes. One can presumably ask the further question as to what exactly is the nature of the entities that play those roles. This allows people to propose rather wild theories about what propositions are. Stalnaker's is a wild theory in my opinion.

2. According to Stalnaker, "a proposition is a function from possible worlds into truth-values." (p. 2) Note that S. says that a proposition is a function, not that it can be represented as one. The latter claim is innocuous; the former is not. But could a proposition be a function? Well, what is a function? A function has an 'argument' and a 'value.' If 2 is the argument of the squaring function, then 4 is the value. If -2 is the argument, 4 is the value. Essential to the notion of a function is that it assigns a unique output or value for each input or argument. A function can be thought of as a rule whereby one assigns a unique member of one set — call it the 'range' of the function to each member of another set — call it the 'domain' of the function.

3. Since everything in mathematics is a set, functions are sets. A binary function is a set of ordered pairs, and in general an n-ary function is a set of ordered n-tuples. So the squaring function is the set of all ordered pairs which set has as members <-3, 9>, <3, 9>, <-2, 4>, <2, 4>, <-1, 1>, <1, 1>, . . . .

A proposition, then, is a set of ordered pairs each member of which is of the form [W, TV] where W is a possible world and TV is a truth-value. Thus the proposition Socrates is wise is the set of ordered pairs which would have the following as members, where 'A' stands for the actual world: [A, T], [W1, F], [W2, T], . . . . Accordingly, a proposition is a monstrous set each element of which is an ordered pair whose first member is a possible world and whose second member is a truth-value. (Read the brackets as angle brackets.)

4. Sets are extensional entities: Two sets are the same iff they have all the same members. Since functions are sets, they too are extensional entities. And since propositions are functions, they also are extensional entities. This implies that two propositions are identical if they are true and false in all the same possible worlds. In other words, necessarily equivalent propositions are identical. As Stalnaker appreciates, this is highly counterintuitive. Surely (to use an example of my own), the Axiom of Choice is not the same proposition as Zorn's Lemma: one can accept the first while doubting the second. To prove their necessary equivalence is a nontrivial problem! One wants to insist that they differ in their very meaning or content. But on Stalnaker's extensionalist approach, this difference evaporates and they must be regarded as the very same proposition.

But there is worse to come. Stalnaker's extensionalism implies that there is only one necessary truth. Let P and Q be necessary truths. Since each is true in all possible worlds, there is nothing to distinguish them extensionally, and so they are identical.

5. But even apart from these difficulties, the very notion that a proposition is a set is absurd on the face of it. While there may be some latitude as to what propositions are, surely there are some things they cannot be, sets for example. Propositions are either trut or false. But it borders on incoherence to say that sets are either true or false. But that is what Stalnaker's view implies.

But much more needs to be said — in the next installment for which you will no doubt be waiting with bated breath. But now I'm off with wifey to the Five and Diner for some greasy American grub in a '50's environment.

The materialist, then, holds that everything is material: not just tables and rocks and black holes and their parts and microconstituents all the way down to the subatomic, but also human beings, their thoughts and feelings, and indeed anything that could be an existent object of their thinking.

If we think of all entities as divisible into three mutually irreducible disjoint categories, the material, the mental, and the abstract, then what the materialist is claiming is that the second two categories are empty. So the materialist is committed to denying the existence of God (as traditionally conceived), disembodied and unembodied minds/souls, unexemplified universals, and all 'Platonic' entities including Bolzano's Saetze an sich, Frege's Gedanken, and the like.

But what do we do with truth? Does it have a place in the materialist's world? Of particular interest is the truth of the materialist thesis itself, the truth of the proposition expressed by 'Everything is material.' If everything is material, then the truth or falsehood of this thesis must also be material. But if we cannot make sense of this, then materialism will be inconsistent with the conditions of its own truth.

There is a difference between truth and a truth. Truth is what is common to particular truths. Perhaps it is a property, the property of being true. (Frege thought otherwise, but his theory is so bizarre that I hesitate to bring it up.) A particular truth, on the other hand, is a true proposition, or, to put it more generally, a true truth-bearer.

So let's inquire into truth-bearers. A truth-bearer (truth-vehicle) is whatever can be appropriately characterized as either true or false. Not everything can be so characterized. A banana cannot be a truth-bearer, since no banana is either true or false. (If you say that a banana that is not fake is true, then you are equivocating on 'true.') But Poindexter's belief, of a particular banana, that it is ripe, is appropriately characterizable as either true or false, whence it follows that beliefs are candidates for the office of truth-bearer.

Other candidates: sentences-tokens, sentence-types, utterance-events, judgments, Fregean propositions. Clearly, nothing can be either true or false unless it has a sentence-like structure. Thus the set {Socrates, wisdom} cannot have a truth-value. And the same goes for {Socrates, Exemplifies, Wisdom}.

Now if a you are a materialist, then your options narrow: you cannot admit as candidate truth-bearers anything irreducibly mental or irreducibly abstract. You have to say that truth-bearers are material objects, whether simple or complex.

Herein lies the rub. It is difficult to understand how any material item, or collection of material items, could be true or false. A belief can be true or false because of its intentionality: it is of or about something distinct from itself; it is a representation. As such, it can represent things as they are, or the opposite. But materialists cannot allow that beliefs (occurrent believings) are irreducibly mental items; the materialist must either go eliminativist and deny the very existence of beliefs, or (more plausibly) attempt to identify beliefs with states of the brain. But a brain state is just a physical state of a physical organ.

Such states can be assigned semantic properties ab extra, but it is difficult to see how they could intrinsically possess semantic properties. How could a physical state be intrinsically such as to represent Bush, say, as hopelessly inarticulate, or Ted Kennedy as irremediably confused?

A similar argument can be deployed for any material item that is advanced as a candidate truth-bearer. Here on this screen are dark characters against a light background. You see these characters with your eyes. But you interpret them as meaningful with your mind. Now the meaning of these meaningful marks is not intrinsic to them as physical scribbles. For this reason it makes no sense to say that a declarative sentence-token is true or false qua string of physical marks.

It seems that we have driven the materialist into a corner. Qua materialist, he cannot admit as existent anything other than material items. But we have just seen that no material item can be either true or false. So there is no room for truths in the materialist's world. There is no room for truth since there is no room for truth-bearers.

It follows that there is no room for the putative truth that everything is material. There is no room for the falsehood of this thesis either. So we ought to conclude that materialism is inconsistent with the conditions of its own truth or falsity. Materialism as defined above is a self-refuting thesis. So it cannot be that the category of material items is the only nonempty category. If it is nonempty, at least one of the others has to be nonempty as well.

The eliminative materialist will reply that that argument makes the same mistake that an ancient or medieval person would be making if he insisted that he could just see with his own eyes that the heavens form a turning sphere, or that witches exist. The fact is, all observation occurs within some system of concepts, and our observation judgments are only as good as the conceptual framework in which they are expressed. In all three cases — the starry sphere, witches, and the familiar mental states — precisely what is challenged is the integrity of the background conceptual frameworks in which the observation judgments are expressed. To insist on the validity of one's experiences, traditionally interpreted, is therefore to beg the very question at issue. For in all three cases, the question is whether we should reconceive the nature of some familiar observational domain.

Even if we grant that "all observation occurs within some system of concepts," is the experiencing of a pain a case of observation? If you know your Brentano, you know that early on in Psychology From an Empirical Standpoint he makes a distinction between inner observation (innere Beobachtung) and inner perception (innere Warhnehmung). Suppose one suddenly becomes angry. The experiencing of anger is an inner perception, but not an inner observation. The difference is between living in and through one's anger and objectifying it in an act of reflection. The act of inner observation causes the anger to subside, unlike the inner perception which does not.

Reflecting on this phenomenological difference, one sees how crude Churchland's scheme is. He thinks that mental data such as pains and pleasures are on a par with outer objects like stars and planets. It is readily granted with respect to the latter that seeing is seeing-as. A medieval man who sees the heavens as a turning sphere is interpreting the visual data in the light of a false theory; he is applying an outmoded conceptual framework. But there is no comparable sense in which my feeling of pain involves the application of a conceptual framework to an inner datum.

Suppose I feel a pain. I might conceptualize it as tooth-ache pain in which case I assign it some such cause as a process of decay in a tooth. But I can 'bracket' or suspend that conceptualization and consider the pain in its purely qualitative character. It is then nothing more than a sensory quale. I might even go so far as to abstract from its painfulness.

Now the existence of this rock-bottom sensory datum is indubitable and refutes the eliminativist claim. For this datum is not a product of conceptualization, but is something that is the 'raw material' of conceptualization. The felt pain qua felt is not an object of observation, but an Erlebnis, something I live-through (er-leben). It is not something outside of me which I subsume under a concept, but a content (Husserl: ein reeller Inhalt) of my consciousness. I live my pain, I don't observe it. It is not a product of conceptualization -- in the way a distant light in the sky can be variously conceptualized as a planet, natural satellite, artificial satellite, star, double-star, UFO, etc. -- but a material or object of conceptualization.

So the answer to Churchland is as follows. There can be no question of re-conceptualizing fundamental sensory data since there was no conceptualization to start with. So I am not begging the question against Churchland when I insist that pains exist: I am not assuming that the "traditional conceptualization" is the correct one. I am denying his presupposition, namely, that there is conceptualization in a case like this.

Most fundamentally, I am questioning the Kantian-Sellarsian presupposition that the data of inner sense are in as much need of categorial interpretation as the data of outer sense. If there is no categorization at this level, then there is no possibility of a re-categorization in neuroscientific terms.

To answer this question we first need to define naturalism. This is not particularly easy, but in earlier posts I have plumped for David Armstrong's definition:

It is the contention that the world, the totality of entities, is nothing more than the spacetime system. . . . The positive part of the thesis, that the spacetime system exists, is perhaps not very controversial . . . . The negative thesis, that the spacetime system is all there is, is more controversial. (A World of States of Affairs, p. 5)

If we accept Armstrong's definition — and I see no reason not to accept it — and if naturalism so defined is true, then the following do not, and presumably cannot, exist: God as classically conceived, disembodied minds/souls, unexemplified universals, and a whole range of objects variously characterizable as ideal, Platonic, or abstract, including Fregean propositions, Fregean senses in general, numbers, irreducible sets, and the like.

In sum, naturalism (N) is the thesis that reality is exhausted by the space-time system. So the question before us can be formulated thusly:

Q. Is there some proposition P such that (i) we know that P, and (ii) P entails ~N?

There are unexemplified universals entails ~N. But do we know that there are unexemplified universals? There are various arguments one can give, and some of them are valid and have plausible premises. But that is not to say that we know their conclusion. Similarly for arguments for Fregean propositions and other items on the above list.

Those of you who would return an affirmative answer to (Q) need to specify some values for 'P.'

Consider the true sentence '2 + 1 = 3' standardly interpreted as a truth of base-10 arithmetic. I say that this sentence is not about physical objects, but about abstract or ideal or 'Platonic' objects. (Forget about the historical Plato and his actual doctrines.) Such objects are neither spatial nor temporal nor mental. To say that they are abstract is to say that they are (i) necessarily existent (existent in all metaphysically possible worlds) and (ii) causally inert: they do not enter into causal relations as either causes or effects. The term 'abtract' is less than felicitous, suggesting as it does a product of a mental act of abstraction; but that infelicity is no part of its meaning in this context.

One way to support this 'platonism' is by considering the defects of alternative views. By 'support,' I mean make a rational case for. I doubt that one can provide 'knock-down' arguments for it. One alternative could be called physicalism. Bill Keezer in an earlier thread made this suggestion if I understood him correctly.

How might one interpret '2 + 1 = 3' physicalistically? One might interpret it as about piles of physical things. Whenever one has a pile of two things, and adds a third, the result is a pile of three physical things. Accordingly, the arithmetical sentence is not about certain platonic objects subsisting in splendid and serene isolation from the flux and shove of the spatiotemporal order; the sentence is an empirical generalization about physical piles. But surely this leaves something to be desired.

Here is a quick consideration. Set-theory is essential to modern mathematics. But it is difficult to see how sets could be identified with piles of physical things. For there are many more sets than there are piles. I've got a pile of two bricks, A and B. Corresponding to that pile is the set, {A, B}. That set has four subsets: {A, B}, {A}, {B}, { }. But they form a set, which is called the power set of the original set, namely: { {A, B}, {A}, {B}, { }}. But there is also the power set of that power set, and so on ad infinitum.

Clearly, there are no physical piles corresponding to all these sets. So sets cannot be identified with physical piles. Sets are mathematical objects. Therefore there are mathematical objects that cannot be identified with physical objects. Numbers are construable as sets. Therefore numbers cannot be identified with physical objects whence it follows that not everything is a physical object!

The author is introducing a discussion of the imaginary number i = the square root of -1. His point is that we are free to introduce this number since all numbers are inventions. So we can make up any number we like. The actual argument given is self-contradictory: The point of saying that numbers do not grow on trees is that they do not occur in nature. But if they live in our heads, then they are part of nature, because what is in our head is part of nature.

But let's be charitable. The argument the author is trying to give is something like this:

1. Numbers are not physical objects
Therefore
2. Numbers are mental constructions.

That this is a non sequitur should be obvious. For there is a third possibility: numbers are abstract or ideal or Platonic objects. This third possibility is seen to be plausible once one considers the difficulties with the view that numbers are mental constructions.

Note first that an abstract object is not one produced by a mental act of abstraction. For present purposes we can say that an abstract object is any entity that necessarily exists but is causally inert.

Note second that a number is not the same as a numeral. One and the same number can be represented by different numerals. Thus the same number is denoted by the Arabic '9' and the Roman 'IX.' Numerals are physical, while numbers are not. So no number is a numeral.

We also note that 9 in a base-10 or decimal system is equivalent to 1001 in a base-2 or binary system. When I speak of the number 9 I am referring to the denotatum of the numeral '9' as this numeral functions within our ordinary base-10 system. That denotatum is the say as the denotatum of '1001' as the latter functions within a base-2 system.

One and the same proposition can be expressed by different indicative sentences. Thus the binary sentence '1 + 1 = 10' expresses the same true proposition as is expressed by the decimal sentence '1 + 1 = 2.' But if the two sentences are both interpreted relative to the decimal system, then they express different propositions, one true and the other false.

Our question is whether numbers themselves are mental constructions, not whether numerals are mental constructions. This is connected with the question of whether mathematics is in any sense conventional. No doubt notation systems are conventional, i.e. decided upon by human beings (or whatever other intelligent critters there might be elsewhere); but it doesn't follow that numbers or other mathematical objects are.

If numbers themselves are mental constructions, then they depend on our existence for their existence. (Forget about extraterrestrial intelligences for the nonce.) The same goes for the truths in which they are involved. (Thus 7 and 9 and 16 are involved in the truth expressed by '7 + 9 = 16'.) But we didn't always exist. Consider a time before any minds existed, some time after the Big Bang and before the emergence of life on earth, say.

During that interval, the speed of light and the speed of sound were the same as they are now, and during that time the former was greater than the latter, as is the case now. Let 'c' denote the speed of light in a vacuum. C is identical to some number, which number depending on the units of measurement one employs. So c = 186,000 miles/sec (approximately). In the metric system, c = 300,000 km/sec (approximately). The point is that once the system of measurement is fixed -- which of course is conventional -- then some definite number is the SOL. Similarly with the speed of sound, SOS. Now

1. SOL > SOS

is true now and was true at the time when no humans existed. Of course, at that time the concept or notion or idea greater than (taken in its mathematical sense) did not exist since concepts (notions, ideas) cannot exist except 'in' a mind. ('In' here not to be taken spatially.) But the mathematical relation picked out by '>' existed. For if it did not, then (1) could not have been true at the time in question. And the same goes for the relational fact of SOL's being greater than SOS. That fact obtained at the time when no minds existed. So its constituents (the numbers and the greater than relation) had to exist at that time as well.

Therefore, mathematical objects cannot be our mental creations.

Ad 1. There are certain data that no one will dispute, whether materialist, dualist, or idealist. Among these data are the various correlations to which Malcolm is referring: stimulate this portion of the visual cortex in such and such a way and the subject experiences phenomenal blue, etc. Intelligent dualists have always been aware of such basic facts as that drinking alcohol alters the quality of one's qualia, that a blow to the head can cause unconsciousness, and the like. It is important to realize that dualists are not in the business of denying obvious facts. The questions are not about the gross facts, but about their interpretation, about what they mean and what they entail. Hence dualists cannot be refuted by citing any obvious facts. Indeed, if dualism could be refuted by citing empirical facts, it would not be a philosophical thesis at all.

I stress this, because many don't understand it. They think that substance dualists deny facts that are well-known or scientifically established. One commenter, for example, compared substance dualists to flat-earthers — which of course shows total misunderstanding.

"Why is this the case, if our minds aren't simply something the brain is doing?" Because it could be the case even if our minds are not simply something the brain is doing. If substance dualism is true, then the mind is a substance. But note the following definition:

D1. X is a substance =df X is metaphysically capable of independent existence.

(D1) lays down what is meant by 'substance' in discussions about substance dualism in the philosophy of mind. That and that alone is what is meant by the term.

Note also that 'substance' has a half-dozen or so meanings and that in this context, 'substance' does not mean stuff. Thus the dualist cannot be blown out of the water by some such cheapshot as saying that he is committed to something self-contradictory like immaterial matter. (Not that Malcolm would reach for such a cheapshot.)

So for the dualist, the mind can exist without being embodied. But my mind, with which I am rather well acquainted, is an embodied mind. It is embodied as a matter of contingent fact, though not as a matter of metaphysical necessity. So it is not surprising that what goes on in my mind affects and is affected by what goes on in my brain and central nervous system. It is not surprising that the states of an embodied mind will be affected by alcohol in the bloodstream. In general, it is not suprising that (some) changes in the brain will bring about changes in the mind.

Since the facts that Malcolm adduces can be explained both materialistically and dualistically,, his adducing of said facts does not support materialism over dualism. Since the facts are consistent with both schemes, they do not entail either scheme.

So what Malcolm says in #1 is not a good reason to reject dualism. Of course, what I said in rebuttal does not provide a good positive reason to accept dualism over materialism. What I have done is merely remove a threat to the rationality of dualist belief.

A fourth reason is that, unlike most other theories of being qua being, physicalism is meant to be criticizable by way of observational testing. According to contemporary physicalists, the principles of physicalism are to be treated as high-level empirical hypotheses or generalizations.

What Post is saying, then, is that the metaphysical proposition

1. To be is to be physical

is an empirical generalization supported by natural science and open to disconfirmation by future experience. Three objections immediately come to mind.

Objection One

The gist of my first objection is that (1) cannot be an empirical generalization. Empirical generalizations, if true, are contingently true. So if (1) is an empirical generalization, then (1) is contingently true. But then it can't be the case that to be is to be physical.

Why not? Well, (1) asserts an identity between the 'property' of being (existence) and the 'property' of physicality. This identity entails the necessary equivalence

2. Necessarily, for any x, x exists iff x is physical.

(One cannot validly move from equivalence to identity, but one can validy infer an equivalence from an identity.)

The upshot is that (1) is both contingently true (because it is an empirical generalization) and not contingently true (because it entails a necessary truth). But this is a contradiction, so (1) is not an empirical generalization.

Once one appreciates this, one sees that physicalism cannot be supported by natural science. In general, metaphysical propositions about being qua being cannot be supported or refuted by naturalistic methods. Natural science cannot take the place of first philosophy.

But couldn't (1) be taken to assert the contingent identity of existence and physicality? I don't see how. Indeed, I have no idea what that could mean. If two individuals are identical, then that is necessarily the case. Contrapositively, if two individuals are possibly distinct, then they are distinct. Similarly, if two properties are possibly distinct, as they would be if they were only contingently identical, then they are distinct. Consider a possible world in which something exists that is not physical, the number 9 say, or perhaps some set of physical objects. In that world existence and physicality are distinct properties. But if they are distinct in one possible world, then they are distinct in all possible worlds, including the actual world.

Second Objection

My second objection is that (1), if true, supplies itself with a counterexample, and thus refutes itself. (1) expresses a proposition, call it P. (I take it to be self-evident that a proposition must not be confused with its physical embodiment whether it be marks on a page or pixels on a monitor.) So if (1) is true, then the proposition P expressed by (1) is physical. But there is no tenable theory of propositions according to which propositions are physical entities.

Frege's Gedanken, for example, despite their name, are Platonic entities and therefore nonphysical. The same goes for Bolzano's Saetze an sich. Suppose you say that propositions are not Platonic entities but exist only as the accusatives of judging minds. Still, such accusatives cannot be intelligibly viewed as a physical entities. They are senses, even if they cannot exist in splendid Platonic independence. Less plausibly, a proposition might be construed as some sort of set-theoretical construction, whether a set of utterance events or a set of possible worlds. But even these far-fetched theories don't help since sets are abstract entities, hence nonphysical.

Propositions, then, cannot be physical. So (1), whether true or false, expresses a proposition, a nonphysical entitiy. Therefore (1) is false: the proposition it expresses is its own counterexample.

Third Objection

My third objection is a circularity objection: (1) is damagingly circular. To see this, ask yourself whether Pegasus is a counterexample to (1). Pegasus is a winged horse. So Pegasus is a physical item. After all, a horse is a physical item, and to add physical appendages to a physical item does not alter its physicality. So Pegasus appears to be a counterexample to (1): Peagasus is physical, but does not exist. To block this and like counterexamples, one must construe (1) as short for

3. To exist = to be physical and exist.

On this construal, (1) is true but circular. This shows that existence cannot be identified with the categorial property of being physical. Indeed, it shows that existence cannot be identified with any property. And this for the simple reason that nothing can have a property unless it exists.

Conclusion

Physical science studies physical reality. But it is in no position to establish that physical reality exhausts the whole of reality. The assertion that to be is to be physical is a meta-physical assertion in that it attempts go beyond physical reality to characterize reality as such. My second and third arguments show that this meta-physical assertion is false, and my first argument shows that it cannot be supported by natural science.

Suppose then that on a particular occasion I am thinking about a certain species of animal, say dogs —- not some specific dog, just dogs in general (but I mean domestic dogs, specifically, not dogs in the generic sense that includes wolves and coyotes). The Martian scientist is present and has his usual complete knowledge of my neurophysiological state. Can he tell on that basis alone what I am thinking about? Can he tell that I am thinking about dogs rather than about cats or radishes or typewriters or free will or nothing at all? It is surely far from obvious how he might do this. My suggestion is that he cannot, that no knowledge of the complexities of my neurophysiological state will enable him to pick out that specific content in the logically tight way required, and hence that physicalism is once again clearly shown to be false.

[. . .]

Suppose then, as seems undeniable, that when I am thinking about dogs, my state of mind has a definite internal or intrinsic albeit somewhat indeterminate content, perhaps roughly the idea of a medium-sized hairy animal of a distinctive shape, behaving in characteristic ways. Is there any plausible way in which, contrary to my earlier suggestion, the Martian scientist might come to know this content on the basis of his neurophysiological knowledge of me? As with the earlier instance of the argument, we may set aside issues that are here irrelevant (though they may well have an independent significance of their own) by supposing that the Martian scientist has an independent grasp of a conception of dogs that is essentially the same as mine, so that he is able to formulate to himself, as one possibility among many, that I am thinking about dogs, thus conceived. We may also suppose that he has isolated the particular neurophysiological state that either is or is correlated with my thought about dogs. Is there any way that he can get further than this?

The problem is essentially the same as before. The Martian will know a lot of structural facts about the state in question, together with causal and structural facts about its relations to other such states. But it is clear that the various ingredients of my conception of dogs (such as the ideas of hairiness, of barking, and so on) will not be explicitly present in the neurophysiological account, and extremely implausible to think that they will be definable on the basis of neurophysiological concepts. Thus, it would seem, there is no way that the neurophysiological account can logically compel the conclusion that I am thinking about dogs to the exclusion of other alternatives.

[. . .]

Thus the idea that the Martian scientist would be able to determine the intrinsic or internal contents of my thought on the basis of the structural relations between my neurophysiological states is extremely implausible, and I can think of no other approach to this issue that does any better. The indicated conclusion, once again, is that the physical account leaves out a fundamental aspect of our mental lives, and hence that physicalism is false.

I will now sum up BonJour's reasoning in my own way. BonJour is thinking about dogs. He needn't be thinking about any particular dog; he might just be thinking about getting a dog, which of course does not entail that there is some particular dog, Kramer say, that he is thinking about getting. BonJour's thinking has intentional content. The question is whether the Martian scientist can determine what that content is by monitoring BonJour's neural states during the period of time he is thinking about dogs. The content before BonJour's mind has various subcontents: hairy critter, mammal, barking animal, man's best friend . . . . But none of this content will be discernible to the neuroscientist on the basis of complete knowledge of the neural states, their relations to each other and to sensory input and behavioral output. Therefore, there is more to the mind than what can be known by even a completed neuroscience. Physicalism (materialism) is false.

'Multiply' is a picturesque way of saying posit. So the principle enjoins us to refrain from positing more types of entity than we need to explain the phenomena that need to be explained. It is obvious that (OR*) does not tell us to prefer theory T1 over theory T2 if T1 posits fewer types of entity than T2. What it tells us is to prefer T1 over T2 if T1 posits fewer types of entity AND accounts adequately for all the data. So there is a trade-off between positing and accounting.

It goes without saying that securing agreement on just what the data are, and whether a given theory accounts for them adequately, is a messy business. It is especially messy when, as is the case here, what one is seeking are philosophical rather than scientific explanations.

How does Occam's Razor bear upon the question of metaphysical naturalism (which is to be distinguished from ethical, epistemological, and methodological naturalism)? As follows. If naturalism accounts for all the data adequately, then I say we should be naturalists. Thus there is arguably a presumption in favor of naturalism, a presumption that rests on the Razor.

Metaphysical naturalism (MN) may be defined as the doctrine that the world, the totality of entities, is identical to the space-time system. This is essentially D. M. Armstrong's definition. (A World of States of Affairs, p. 5.) If MN is true, then there is no God as classically conceived, no unembodied or disembodied finite minds, no abstracta or Platonica such as Fregean propositions, and no unexemplified universals. (MN as defined does allow for immanent physical universals: see Armstrong.)

Some identify MN with atheism, the denial that God as classically conceived exists. That is a mistake in my book: MN entails atheism, no doubt, but is not logically equivalent to it, since atheism does not entail metaphysical naturalism. McTaggart was an atheist but not a metaphysical naturalist.

Suppose there are three candidate entity-types, basic and mutually irreducible: bodies, minds, abstracta. The naturalist can be understood to be saying that the second two categories are empty and that their members are not needed to explain the data.

It follows that there are several ways to be an anti-naturalist. One way is to say that we need minds and bodies but not abstracta. Another is to say that we need bodies, minds, and abstracta. A third is to say that we need bodies and abstracta but no minds. A fourth is to say that we can get by just with minds. (Berkeley, McTaggart) A fifth is to say that we need only minds and abstracta. A sixth is to say that we can scrape by on abstracta alone. (I seem to recall a logician named Fitch who thought everything is at bottom a proposition or a construction out of propositions -- but I could easily be wrong about that.)

From the foregoing it should be clear that Occam's Razor does not support MN by itself, but only together with an antecedent acceptance of bodies as irreducibly real. But given the latter acceptance, then OR* enjoins us to try to explain the data without invoking irreducible minds or mental contents (qualia, e.g.) or abstracta.

So this is what I am interested in discussing: Can naturalism explain everything that needs to be explained? If it can, then we ought to be naturalists, or at least the pressure is on to accept naturalism. God might still exist even if everything apart from God could be explained without reference to God. But then what reason would one have to posit God? Mystical experience of God? God's self-revelation through his prophets as recorded in scripture? Perhaps, but then the question of the veridicality of these sources of putative knowledge becomes very pressing indeed. Metaphysical naturalism will most like bring epistemological naturalism and scientism in its train and thus a foreclosing on all sources of knowledge apart from science.

So I say that the pressure is on to accept naturalism if it can explain what needs to be explained. Of course, I don't think it can explain what needs to be explained, which is why I am an anti-naturalist. I am not an anti-naturalist because I am a theist, I am an anti-naturalist because naturalism fails to explain what needs to be explained. I have been building my case slowly, but it is far from complete.

But note well: to argue against naturalism is to not argue for substance dualism. For there are other options such as absolute idealism. If everything is a mind or a content in a mind, then that is as parsimonious an explanation as an explanation that states that everything is either a body or a construction from bodies.

What needs to be explained? This requires a separate post.

Since there is a presumption in favor of naturalism, it is appropriate to proceed as I have been proceeding, namely, challenging naturalists to show how their theories work and account for the data. Pollack et al. may feel this to be unfair because I have them on the defensive; but it seems to me that the presumption in favor of naturalism makes to reasonable to see if we can be satisfied by it. If we can, then there is no need to posit anything beyond the natural.

Note also -- and this may apply to Kevin Kim -- the untenability of substance dualism, say, does not show the tenability of naturalism. After all, they could both be false and/or untenable.

1. I am assuming that our cognitive faculties are reliable. Thus my question is not whether they are reliable, but whether it is rational to hold that they are reliable if one also holds they are the accidental products of blind evolutionary processes.

2. By 'reliable,' I mean reliable for producing true beliefs more often than not when our faculties are functioning properly in their appropriate environments. A true belief is one that corresponds to the way the world is in itself. If my belief that a is F is true, then a is F -- whether or not anyone believes it. Truth puts one in touch with reality.

3. Reliability is a normative concept. Compare trustworthiness. To say that a person is trustworthy is not merely to say that the person CAN be trusted, but that he is WORTHY of being trusted, that he deserves trust or merits trust. (Anyone who is trusted, can be trusted; but this is not to say that anyone who is trusted is trustworthy.) Hence to say that our cognitive apparatus (inner sense, outer sense, discursive reason, and whatever else one wants to include) is reliable or trustworthy is not to say that we as a matter of fact rely or have relied on it, or that we can rely on it, but that we are justified in relying on it due to a certain intrinsic aptness of the faculty for producing true beliefs. A reliable faculty is one that is worthy of being relied upon to produce true beliefs.

4. Pollack says in effect that it is rational to trust our faculties to produce true beliefs because such trust has proven to have survival-value. Although it is true that we and our faculties have arisen by accident via blind evolutionary processes from less complex forms of life, our faculties are nonetheless reliable because we have been relying on them and we have been successful in the struggle for existence.

5. If this is what Pollack means -- and it may not be -- then I think a mistake has been made, namely, an illicit inference from the factual assertion that our reliance on our faculties has worked out well as far as survival as a species goes to the normative assertion that our faculties are worthy of being relied upon to produce true beliefs.

I don't see how success justifies. I don't see how one validly moves from (a) Trusting our faculties, we have been successful to (b) Our trust in our faculties is justified. For if our faculties arose by accident, then it is sheer chance, a mere contingent fact, that so far they have been productive of true beliefs. If they weren't designed to track truth, but merely have happened to track truth so far, then we have no reason to trust them.

6. I don't believe it will do any good for Pollack to say that our faculties did not arise by accident but were designed by mindless processes, or anything along those lines. (Compare Dennett's silly talk of Mother Nature designing this and that.) For that is to misuse the word 'design.' To be designed is to be designed for a purpose by a being who is purposive. Something that arises from natural selection operating upon random mutations may appear to be designed, but it makes no sense to say that such a thing is designed. Thus the heart appears to have been designed for a purpose, namely, to pump blood. But the mere appearance of design does not entail design, and if the heart came about by undirected evolutionary processes, then the corrct thing to say is that the heart was not designed, and that the appearance of design is a mere appearance and no part of reality.

7. So I persist in my view that it is not rational to hold BOTH that our cognitive faculties are reliable, AND that they are accidental products of blind evolutionary processes.

Of course, the two rock piles might have come into existence via purely natural causes: a rainstorm might have dislodged some rocks with gravity plus other purely material factors accounting for their placement. Highly unlikely, but possible. This possibility shows that the appearance of design does not entail design.

Nevertheless, your taking of the rock piles as trail markers presupposes (entails) that they are designed. It would clearly be irrational to take the piles as evidence of the trail's direction while at the same time maintaining that their formation was purely accidental. And if you found out that they had come into being by chance due to an earthquake, say, you would cease interpreting them as meaning anything, as providing information about the trail. One must either take the cairns as meaningful and thus designed or as undesigned and hence meaningless. One cannot take them as both undesigned and meaningful. For their meaning -- 'the trail goes that-a-way' -- derives from a designer.

Now consider our incredibly complex sense organs. We rely on them to provide information about the physical world. I rely on eyesight, for example, both to know that there is a trail and to discern some of its properties. I rely on hearing to inform me of the presence of a rattlesnake. I rely on my brain to draw inferences from what I see and hear, inferences that purport to be true of states of affairs external to my body. The visual apparatus (eye, optic nerves, visual cortex and all the rest) exhibits apparent design. It is as if the eyes were designed for the purpose of seeing. But the appearance of design is no proof of real design. And indeed, human beings with their sensory apparatus are supposed to have evolved by a process of natural selection operating upon random mutations. If so, eye and brain are cosmic accidents.

But if this is the case, how can we rely on our senses to inform us about the physical world? If eye and brain are cosmic accidents, then we can no more rely on them to inform us about the physical world than we can rely on an accidental collocation of rocks to inform us about the direction of a trail.

As a matter of fact, we do rely on our senses. Our reliance may be mistaken in particular cases as when a bent stick appears as a snake. But in general our reliance on our senses for information about the world is justified. Our senses are thus reliable: they tend to produce true beliefs more often than not when functioning properly in their appropriate environments. We rely on our senses in mundane matters but also when we do science, and in particular when we do evolutionary biology. The problem is: How is our reliance on our sense organs justified if they are the accidental and undesigned products of natural selection operating upon random mutations?

To put it in terms of rationality: How could it be rational to rely on our sense organs (and our cognitive apparatus generally) if evolutionary biology in its naturalistic (Dawkins, Dennett, et al.) guise provides a complete account of this cognitive apparatus? How could it be rational to affirm both that our cognitive faculties are reliable, AND that they are accidental products of blind evolutuionary processes? I agree with Richard Taylor who writes:

. . . it would be irrational for one to say both that his sensory and cognitive faculties had a natural, nonpurposeful origin and also that they reveal some truth with respect to something other than themselves, something that is not merely inferred from them. (Metaphysics, 3rd ed. p. 104)

This suggests the following design argument:

1. It is rational to rely on our cognitive faculties to provide access to truths external to them.

2. It is rational to rely on our cognitive faculties only if they embody the purposes of an intelligent designer.

Therefore

3. Our cognitive faculties embody the purposes of an intelligent designer.

To resist this argument, the naturalist must deny (2). But to deny (2) is to accept the rationality of believing both that our cognitive faculties arose by accident and that they produce reliable beliefs. It is to accept the rationality of something that, on the face of it, is irrational.

Similarly, the claim that something - say the bacterial flagellum - is too complex to have evolved by natural selection is alleged, by a lamentably common but false syllogism, to support the "rival" intelligent design theory by default. This kind of default reasoning leaves completely open the possibility that, if the bacterial flagellum is too complex to have evolved, it might also be too complex to have been created. And indeed, a moment's thought shows that any God capable of creating a bacterial flagellum (to say nothing of a universe) would have to be a far more complex, and therefore statistically improbable, entity than the bacterial flagellum (or universe) itself - even more in need of an explanation than the object he is alleged to have created.

Observe first of all that there is a difference between what Dawkins and Coyne impute to the proponent of ID, namely, "the bacterial flagellum is too complex to have evolved" and what they should have imputed to him, namely, "the bacterial flagellum is too complex to have evolved by natural selection." The proponent of ID, as I understand the position, need not deny evolution construed as the fact of common descent with later forms of life arising from earlier ones by numerous successive and slight modifications. What the proponent of ID questions is the mechanism of this descent, namely, natural selection. The question is whether there are forms of organizational complexity that cannot be accounted for by natural selection.

Once this is appreciated, it is easy to see that if something is too complex to have evolved in one way, by natural selection, it does not follow that it is too complex to have evolved in another way, i.e., by being created by an intelligent designer.

Dawkins and Coyne, however, think that ID is involved in an error of reasoning. What the proponents of ID are doing is giving a circular explanation. To be explained is a complex entity, the bacterial flagellum say. But the entity invoked in the explanation is itself a complex entity. So complexity is being explained in terms of complexity -- which is circular. Thus they write,

If complex organisms demand an explanation, so does a complex designer. [. . .] the "default" logic of the creationists remains thoroughly rotten.

But this shows a complete misunderstanding of what the proponent of ID is doing. It would be circular to try to explain complexity in terms of complexity. But it is not circular to explain one form of complexity in terms of another. The complexity that needs to be explained is the complexity that seems to have been designed. To invoke a crude analogy, it is not the complexity of a pile of rocks that needs personal explanation, but the complexity of a cairn, a pile of rocks whose assembly shows that they mark the trail. Now I cannot account for a pile of rock's being a cairn by invoking natural processes; I need to invoke an intelligent designer, a person such as a trail-blazer or trail-maintainer. Of course, this person is even more complex than his product. But there is no circularity since material complexity is not being explained by material complexity but by the thoughts, intentions and actions of a person. Material complexity is being explained by personal complexity. Hence there is no circularity in the explanation.

It is also worth pointing out that if A explains B, the explanation can be good even if A remains unexplained. Why so many wildfires this year? Because of a profusion of brush which in turn was caused by unusual spring rainfall. If this is a good explanation, its goodness does not require an explanation of why there was an unusual amount of rainfall.

So as far as I can see the proponent of ID is not committing any logical error. Dawkins is simply mistaken to accuse the IDist of "thoroughly rotten" logic. Of course, the IDist is violating a rule of natural science, namely the rule that everything be accounted for naturalistically, i.e., in terms of the space-time system and the laws that govern it. Thus living processes must be explained using the same laws as govern nonliving processes. One is no longer playing the scientific game if one invokes irreducible mentality or irreducible vitality.

But to violate the rule I just mentioned is not to violate any logical rule.

And it's no solution to raise the theologian's plea that God (or the Intelligent Designer) is simply immune to the normal demands of scientific explanation. To do so would be to shoot yourself in the foot. You cannot have it both ways. Either ID belongs in the science classroom, in which case it must submit to the discipline required of a scientific hypothesis. Or it does not, in which case get it out of the science classroom and send it back into the church, where it belongs.

If natural science must play by the rule mentioned above to be natural science, then ID is not natural science. To invoke an irreducibly intelligent designer (whether or not identical to God as traditionally conceived) is to invoke something that is not a mere part of the space-time system. But it is equally true that evolutionary biology is not strictly science either since it rests on philosophical assumptions that cannot be justified scientifically. Naturalism, the thesis that nothing (or perhaps nothing concrete) exists apart from the space-time system is a philosophical thesis. Cognate doctrines such as physicalism and scientism are also philosophical, not scientific doctrines strictly speaking. So I conclude as follows:

If ID should be removed from the science classroom and relocated in church, then Dawkins' evolutionary biology should also be removed from the science classroom and relocated in the philosophy lecture hall. For neither is science strictly speaking. But before Dawkins is allowed in the philosophy lecture hall he must take some logic courses. (You will have noticed above how refers to a syllogism as false -- that is logically inept.)