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I think this is a pretty important distinction that I wish had come out more clearly.

Arguments from Reason

When Reppert turns to the argument from reason itself, he does a good job of guiding us through the issues. The argument on p. It is really the same argument that Socrates used at his defense: How can you believe in flute playing and not believe in flutes? How can you believe in divine effects and not believe in the gods? Reppert has updated it and applied it to the existence of reasons in a useful and persuasive manner.

His refutation on pp. The "inadequacy objection," which argues that non-scientific explanations do not explain, is one of the biggest hurdles the argument from reason has to face. Reppert's question on p. When I tried to update Lewis's argument in "Some Propositions for a Theistic Argument," Bulletin of the Evangelical Philosophical Society , : , I focused on the fact that a naturalist universe is by definition a deterministic universe.

The laws of physics determine everything because the universe, being uncaused, exists a se and therefore by definition cannot be other than it is. It seems to me that this fact needs to be stressed, for it provides a simpler way of defeating Anscombe's objections. It really doesn't matter whether chains of reasoning caused by non-rational causes can happen to have been valid or not, unless we are free to choose between them on a non-deterministic basis.

Computing has become more sophisticated, with electronic switches in microcircuits replacing holes and cogs, but the nature of the process has not changed. Physical representations of data are input, causing physical changes to occur in sequence. At the end of this causal chain other representations are output. In the case of the human mind or brain, physical representations of propositions are input just as with a computer.

After that, however, what do the work of causing a belief are sometimes, at least the propositions as such. If physical representations of propositions -- as opposed to the propositions themselves -- do all of the cause-and-effect work of generating my beliefs, then necessarily my beliefs are not generated by propositions. The rationality of all of my beliefs would be compromised under the second corollary of reason , above.

C. S. Lewiss Dangerous Idea: In Defense of the Argument from Reason download

The belief that only natural causes can affect the state of the brain, for example, could not be caused by arguments about the sufficiency of natural causes. To confirm the intractability of this difficulty for naturalism, recall from our previous consideration of intentionality that the aboutness of a sentence cannot be identified with the sentence's physical properties.

Yet those properties are precisely what must do the work of generating states in a natural system. We can summarize:. Perhaps there is an escape hatch for naturalism regarding statement No. If the representations it refers to are caused by propositions then it can still be said that propositions can cause functional states, albeit indirectly. However, this gambit requires us to back up in the causal chain to some system that is not merely computational, that is, to a system in which propositions rather than just representations do causal work.

We are faced with infinite regress if we merely back up from one computational system to another. So far the argument has no obvious naturalistic solution [4]. Here we will pause to take a closer look at the second corollary of reason set forth above.

The AfR as I have outlined it is strengthened by that corollary even though it will stand without it.


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  5. C. S. Lewis's Dangerous Idea: In Defense of the Argument from Reason by Victor Reppert.
  6. C S Lewiss Dangerous Idea In Defense of the Argument from Reason by Victor Reppert Information.

The second corollary of reason states that rationality depends upon correctly perceiving the grounds for beliefs. One might argue that we can rationally believe a proposition without perceiving good reasons for our beliefs. All of us believe some scientific propositions, for instance, that we are incapable of justifying in detail. To hold a belief on the basis of authority does not of itself disqualify a belief as rational. Most of us can offer good reasons for generally trusting, not just the consensus pronouncements of science, but also other authoritative opinions for which we cannot offer detailed explanations.

What about beliefs based on guesses and intuitions? These may be truthful even when cloaked in rationalizations that the holder mistakes for logical grounds. Suppose a juror perceives the evidence of a criminal defendant's guilt, as presented by a prosecutor, to be more conclusive than it actually is because of having subconsciously picked up clues from the defendant's body language and speech patterns.

Can't the juror's belief be considered rational, arising as it does from the guilt of the defendant? I do not believe that it can unless the intuition is made the subject of rational reflection or discussion. The juror may say to himself or others, "Something about the defendant makes me feel that he is untrustworthy, and I have learned from experience that my feelings about people are usually right. Or imagine that we try to persuade someone else of the truth of a belief that we hold.

We present what we think are good reasons but the person remains unconvinced. Perhaps the person replies that our case is weak, that our arguments are inconsistent, or that reasons weighing against our position seem to be stronger than those in its favor. These responses allege that we are mistaken, but they do not impugn altogether our rationality in holding the belief.

But suppose instead that this person claims that we do not hold the belief for the reasons that we think we do. We would be foolish to insist that even if our opponent were right, we might nevertheless be rational in maintaining the belief. Knowing the reasons for our beliefs is part of what it means to have reasons, and having reasons for believing is part of what it means to believe rationally.

It is conceivable that few of our beliefs are purely rational, even though many of them are true. Perhaps some that have little rationality are nevertheless in some mysterious way worthy of belief. But it is difficult to deny that what we rationally believe is rational only insofar as we discern why we believe as we do, and this fact reinforces the AfR. What I have outlined to this point is an updated version of Lewis's argument cast in computational terms.

It refutes the second of our two corollaries of naturalism , but only to the extent that belief states cannot be wholly dependent upon natural brain states. The door is still open for natural states to be necessary conditions for rational beliefs, at least in creatures such as human beings.

The findings of cognitive and neuroscientific research continue to have explanatory value, but it is conceptually impossible for science to explain human reason completely in terms of biochemical states. We will return to the relevance of scientific explanations again below. He says that if naturalism were true then the propositional content of one mental state could not be the cause of another state such as a rational belief. Since rational beliefs must be caused by the propositional contents of earlier mental states, naturalism cannot be true. Carrier's responses to the argument are revealing.

First, he attempts to associate propositions with virtual models, which as we saw previously he considers to be physical:. Propositions are formulated in a language as an aid to computation, but when they are not formulated, they merely define the content of a nonlinguistic computation of a virtual model. In either case, a brain computes degrees of confidence in any given proposition, by running its corresponding virtual model and comparing it and its output with observational data, or the output of other computations.

Thus, when I say I "accept" Proposition A this means that my brain computes a high level of confidence that Virtual Model A corresponds to a system in the real world or another system in our own or another's brain, as the case may be ; while if I "reject" A, then I have a high level of confidence that A does not so correspond; but if I "suspend judgment," then I have a low level of confidence either way. We have touched on the problem with such a claim. Consider a physical object, say, a ship.

A ship can be made in various shapes and sizes out of various materials, but it has certain defining characteristics that can be seen and measured, and a function that can also be measured. So it is with a tree, a thunderstorm, or a chemical reaction. All natural objects, events, or states have features, sometimes even emergent features, which can be sensed or detected and measured.

The Argument from Reason

And the features that we can detect and measure make the object what it is in natural terms. So, what detectable features make a virtual model what it is, and what is the measurable content of such a model? If that which makes a virtual model what it is can only be perceived by introspection, then under naturalistic assumptions it cannot cause changes in a natural system.

Later in his essay, Carrier specifically cites and then addresses Reppert's argument about the propositional content of mental states as follows:. The state of accepting the truth of a proposition plays a crucial causal role in the production of other beliefs, and the propositional content of mental states is relevant to the playing of this causal role. Brains are computers. As such, the output of one computation including the output of confidence level is often physically the input of another computation, and it thereby has a causal effect on that other computation's output.

Every conscious computation in the brain is the computation of either a virtual model or data physically connected to or computed from a virtual model such as a confidence level. Since a proposition literally is the content or output of a virtual model, propositional content therefore literally has a physical-causal effect on further computation that relies on that virtual-model computation which literally is the "proposition" in question.

The claim here that "a proposition literally is the content or output of a virtual model" is remarkable. Elsewhere in his essay Carrier makes it clear that virtual models are not just constructed by the brain but by actual computers as well [5]. And he also leaves no doubt that by "literally" he also means "physically," since he says that output is "often physically the input of another computation. Let's say that the output of a computation is the printout of a proposition. Physically the output is carbon toner and cellulose paper.

So the natural properties of carbon and cellulose must be, in some respects, the natural properties of the proposition. Worse yet, if the proposition is the same as the meaning of its representation, and if the proposition consists of carbon and cellulose, then the meaning of the representation must consist of carbon and cellulose. This makes no sense. We can substitute electrical impulses in circuitry for carbon and cellulose and it still makes no sense. We will be generous here and take Carrier to be saying, not that a proposition literally is the physical output, but that it is realized in the physical output.

A triangle, for example, can be realized in wood or plastic or glass. A ship, as stated earlier, can be realized in wood or steel. Perhaps a proposition can be realized in carbon and cellulose. On second thought, that won't work either. A triangle cannot be realized except as an object with triangularity. The English word "triangle," by contrast, has no triangularity. Likewise, to be the realization of what a ship is, an object must be able to float or be intended to float. It must be sufficiently shiplike. But the word "ship" need not be shiplike at all to represent what it does. Representation, therefore, does not entail realization, much less identity.

Carrier's attempt to naturalize propositions or propositional content must be judged a failure, and as a consequence the bulk of his extensive analysis collapses. It cannot be salvaged by his many references to scientific opinions about human cognition, nor by his frequent criticism of Reppert for failing to pay sufficient attention to such information. The AfR is not, as Carrier implies, an argument from scientific ignorance. It should be apparent by now that the AfR identifies logical constraints on our understanding of the relevant scientific facts.

A paper written in by two cognitive researchers, Richard Nisbett and Timothy Wilson, reveals the conceptual limits on scientific analysis of cognition [6]. Nisbett and Wilson surveyed experiments in which test subjects were monitored for their reactions to various controlled situations and then afterward asked why they had reacted in the way that they did. Evidence showed that in a wide range of circumstances people had reacted for reasons different than those which they later reported.

Some of these situations called for problem solving and reasoned judgment. For example, experiments have shown that the willingness of someone in a room to come to the aid of someone else in an adjoining room who sounds as if they are in distress diminishes as the number of bystanders increases. Subjects in a crowded room are typically slow to offer aid, but when questioned later they deny that the number of people around them had anything to do with their decision not to act.

Other studies found that ratings of stocks by brokers, and diagnoses of illness by therapists, surprisingly poorly reflected the relative importance of the various criteria according to which they reportedly made their judgments. The article contains a list of other similar findings. Nisbett and Wilson go so far as to state, "The evidence reviewed is then consistent with the most pessimistic view concerning people's ability to report accurately about their cognitive processes" [7]. Elsewhere in the article they moderate this claim, but think about what it would mean for us to accept it without qualification.

Or more properly, think of how impossible it is for us to do so. What happens when we apply this assessment recursively to the judgments of Nisbett and Wilson themselves? If we were to ask the authors why they arrived at the conclusions expressed in their paper, presumably they would say that they were led to them by rational analysis of the experimental results they cited. But if we had grounds for doubting their self-report then the reasonableness of the paper's conclusions would be open to question.

We could ourselves check to see whether the evidence in the paper supports the judgments it contains, except that absolute skepticism about cognitive introspection would cast doubt on our own judgment as well. Nisbett and Wilson could argue that rigorous scientific methods, measurements, and records can correct for our failures to appraise accurately our own mental processes.

However, the belief that scientific tools can play a corrective role is itself the kind of judgment that will not survive a universal indictment of introspective knowledge. So there is a limit to how much skepticism science can ever engender regarding our perceptions of our own cognitive processes. We cannot judge as reasonable a finding that denies us the ability to make reasoned judgments, or even one that under logical analysis is found to entail such a denial. Although this paper was written specifically in response to Richard Carrier's review, there are points that Carrier does not touch on that are important enough to the AfR in general to warrant attention here.

In support of C. Lewis and Victor Reppert, I have argued that while rational processes are conditioned by physical activity in the brain, they cannot be fully explained by it. This implies that when the right physical conditions are present, something nonphysical can occur. We can illustrate this with a compass.

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When the pieces of a compass are assembled carefully, the needle begins to be acted upon by a force that cannot be detected during the assembly process. Admittedly, tough questions need to be answered by anyone who proposes that nonphysical, rational processes have physical effects on natural systems such as brains. But first we must consider a philosophical position, epiphenomenalism, which allows for genuinely rational beliefs but denies that they have any physical effects.

Epiphenomenalism is too pessimistic a philosophy to be popular, but refuting it will give us more reason to believe that interaction between the mental and physical sides of reality does occur. Consider a person's act of blinking when an object comes flying toward his or her face. Because eyes are delicate enough to be injured even by light impacts, closing the eyes quickly when a projectile comes toward them is a rational thing to do.

I may acknowledge the rationality of blinking under such circumstances and even form the intention to do so. When a spray of liquid from a pressurized soda can comes suddenly at my face, however, I will blink reflexively. The correspondence of my act of blinking to my belief that it is a reasonable thing to do and even the harmony between my blinking and my intention to blink do not change the fact that the blink occurs for reasons other than my belief and intention.

Epiphenomenalists propose that what is true of my blinking is true of all of my behaviors without exception. It may seem as though my beliefs and intentions cause my actions, but that is a misperception. While I am consciously believing and intending, the unconscious but sophisticated computational processes of my brain are making my arms and legs move, my mouth speak, and my fingers punch the keyboard. Epiphenomenalists admit to two great, probably insoluble, mysteries. The first is conscious experience itself.

The second is the alignment of conscious experience with behavior. But having accepted these two mysteries, they avoid others. They need not assume the Herculean labor of naturalizing beliefs, desires, purposes, and intentions. Neither must they struggle to maintain closure of physical causes against problematic interference from the mental side.

Technically, epiphenomenalism is dualistic because it separates nonphysical experience from physical behavior, but it is a tame dualism that does minimal damage to naturalistic assumptions. The logic of epiphenomenalism, though hard to accept, is easy to grasp. Any behavior can conceivably be programmed, but it is not clear how beliefs, desires, and intentions can be programmed [8].

I can program a computer to respond to an e-mail, but how can I or anyone else program the computer to respond intentionally rather than unintentionally? If the survival of the computer depended on a response that programming was sufficient to ensure, what role is left for intentions to play? Substitute organism for computer and the argument is complete. The fatal flaw in epiphenomenalism lies in the experience that we all have that we intend some actions and not others. Deciding to read a book as opposed to watching television is intended or volitional, while blinking at a sudden spray of soda is not.

Epiphenomenalists' only explanation for the experience of volition -- that it is an illusion -- must be examined critically. Coherence is the minimum requirement for any philosophical conclusion, and to determine coherence in the present instance requires a brief analysis of the relationship between experience, conceivability, and reality. In his Treatise of Human Nature , the philosopher David Hume observed that experiences take the form of impressions that can be simple or complex [9]. His example of a simple impression is the sight of a patch of red color. A more complex impression, he says, might be the collage formed by the sights and sounds of a city.

He notes that complex impressions might be of objects that do not exist. He cites the example of the New Jerusalem described in the Bible, a city with golden streets and buildings made of jewels. How is it, Hume asks, that he can form an impression of something that he has never seen? Hume goes on to show that the answer lies in the complex nature of an imaginary construct.

There are such things as city streets and such a thing as gold, and by combining them we may form a mental picture of something that does not literally exist. Another example is the unicorn. There are no horses with horns growing out of their heads, but because there are real horses and real horns we may combine our impressions of them into a mythical beast. What is true of imaginary constructs is true of illusions. An example is the "moon illusion," in which we misperceive that the image of the moon occupies a larger area of the nighttime sky when it is near the horizon than when it is overhead.

Differences in size both of visual images and of objects as such can be real, and objects in the sky can indeed be seen, but the moon illusion incorrectly conjoins these impressions. An intriguing fact about impressions -- what today might be called percepts -- is that as we move from complex instances to simple ones it becomes progressively harder to conceive of the possibility that they are unreal. Look at the following statements:. In the first case, if we seem to remember a brown horse with white spots on the ears we might be mistaken. The second example is harder to contemplate, but perhaps a rare, undiagnosed ocular dysfunction has misled us into seeing black and gray horses as brown.

With the last statement we have reached the frontier of coherence. It is inconceivable that the color brown does not exist, but why? Had I been born profoundly color blind I would know brown only at second hand. The claim that brown does not exist, while less than plausible, would be conceivable for me. Or say that brown, instead of being a common characteristic of the visual landscape, were a fabled color so pleasing to the eye that it becomes the favorite of anyone who looks at it.

In that case our knowledge of brown would owe to a complex idea combining the simple impressions of sight, color, pleasure, and relation. As it is, most of us are acquainted with brown by sight. Our idea of it owes to a simple impression, as Hume would say, which is why a denial of its existence defies conceivability and falls short of coherence.

We can draw an analogy to language, specifically to words and propositional statements. A statement can be judged as false because it can be broken down into simpler units that convey meaning faithfully. Once we reach the smallest semantic units, the individual words, we can cast doubt on them only by impugning our ability to assess the truth or falsehood of the statement they comprise.

Take the statement, "One of the words of this sentence does not have the meaning that it appears to have. If the statement were true, it could not mean what it appears to say, which would then mean that it is not true. Internal dissonance of this kind is called self-referential incoherence. Famous examples are the liar's paradox "I never tell the truth" and Russell's set paradox [10]. Because we know the color brown from a simple impression, the claim that brown does not exist is incoherent.

It asks us to draw upon our knowledge of brown while denying the basis of that knowledge. Note, however, that although the claim that brown is altogether illusory cannot be true, the possibility remains that the apparently brown color of an object may be illusory in a particular instance.

The reason for this analysis of the complex nature of fantasies and illusions is that epiphenomenalism, as we saw above, denies that mental states as such can have physical effects. Nevertheless, our knowledge of the difference between intended and unintended actions comes from a simple impression; therefore its denial is incoherent. Whether we label the object of this impression as "will" or "volition" or "agency," it cannot be broken down into perceptual pieces that our minds could have incorrectly stitched together.

But just as with the existence of the color brown and brown objects, our present argument leaves open the possibility that the deliberate nature of our actions may be illusory in particular instances. Since volition must be real, the epiphenomenalist's argument leads in an unexpected direction. Programming might be sufficient to explain behavior divorced from experience but not behavior as related to experience.

This can only mean that our experience is incompatible with a purely computational or even functional model of mental processes. This is the same conclusion that the AfR yielded in the preceding section. We now have two independent lines of argument both showing the inadequacy of a naturalistic account of mental activity.

Granted that mental activity is dependent upon but not identical to chemical reactions in the brain, how can it be imagined to influence those reactions? A majority of philosophers doubts that mental processes can, without being physical, exert physical influence. To understand why the majority is wrong on this issue, return for a moment to the work of David Hume.

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Part of Hume's continuing legacy is his demonstration that physical cause and effect do not carry the force of logical necessity. If I light a match and touch it to my finger, it is a matter of logical necessity that the flame cannot simultaneously burn my finger and not burn my finger. But that the flame does burn my finger is not logically necessary. The burning of my finger is an event that happens to occur but does not have to occur, at least not out of logical necessity. Hume's discovery, which we will discuss further below under the problem of induction, has survived every attempt at refutation.

The philosophy of science as a whole continues to accept that physical causes are not linked to their effects by logical necessity. Hume made this discovery purely though reflection, however. No one, least of all Hume himself, anticipated that science would one day provide support for his conclusion. It was able to do so because Hume's analysis of cause and effect implied the possibility of physical events occurring in the absence of physical causes. In the realm of philosophy, Immanuel Kant failed to embrace Hume's radical views on causation and thought that the mechanistic physics model of Newton was logically inevitable.

If relativity undermined this assumption, quantum theory demolished it. Quantum physics stunned the scientific community of the early twentieth century. Karl Popper, the prominent philosopher of science, struggled with it. Einstein famously rejected it, even though he helped to lay its foundations. The significance of quantum physics to our present discussion is not that it provides a mechanism by which mental events can affect natural processes, but that it undercuts all arguments that implicitly give physical causation the status of logical necessity.

Many readers will be familiar with the basics of quantum theory.

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I invite those who are not to imagine a large barrel full of liquid with a small hole near the bottom. If we know the size of the barrel, the size of the small hole, the density and viscosity of the liquid, and other physical variables, we can calculate with a high degree of precision how much liquid will leak out of the hole in a given period of time.

What is true of the barrel is roughly true of a lump of uranium , if we substitute the composition of the atomic nuclei for the characteristics of the fluid and refer to a flux of radiation rather than to leakage. Both of these examples confirm our common sense view of cause and effect because they exhibit uniformity. The leakage rate will be similar for two similar barrels of fluid, and likewise the flux of radiation from two comparable lumps of uranium. The strangeness begins when we scale down to two atoms of uranium instead of two lumps. In spite of the atoms having identical compositions, one may decay in the next minute while the other remains undecayed for the next million years or more.

Common sense tells us that there is some undetected difference in the two atoms that accounts for their different times of decay, but common sense is wrong. How can this be? To find out, let's turn from barrels to photographs. We take a photograph and in looking at the print see that edges of the image are not entirely crisp. Was the focus incorrect? Did the camera move? We photograph the same object over and over and make estimates of the possible camera movement and focal errors, but neither these nor imperfections in the film account for all of the fuzziness.

On the other hand, we can still easily determine the shape of the object in the photograph, which is relatively large. As we photograph smaller and smaller objects, the fuzziness occupies a larger portion of the image until nothing is visible but a blurry smear. Does the extremely small object have a distinct shape that does not register, or does the information consisting of the object's shape simply not exist? This illustrates, in an admittedly rough way, the problem that early twentieth-century scientists encountered as they tried to gather information about subatomic particles.

To continue with our photographic illustration, suppose we determined that the fuzziness of our image was not the result of technical deficiencies. Suppose instead that it proved to be theoretically unavoidable when registering an image by reflection of energy. This discovery would be doubly disturbing because the concept of shape is impossible to divorce from registration. If an object can never in principle register a shaped image then we are forced to conclude that the object is shapeless.

Likewise, the vast majority of physicists have concluded that information we routinely find in large objects and states is lacking at the subatomic level. My blog doesn't see much action if you want to travel over there unless you prefer it at yours. Before we get into things, as I hope you're interested, can you tell me a bit more about yourself? It helps me to understand that I'm conversing with a human and not merely a machine. Thank you for your reply! Hi Chad Sure, I love that kind of thing. You can start off on your blog if you'd like, and then I'll either comment there or reply at my own blog and put a notice on yours.

Last time I had an on-line "exchange" like this So the upshot is that I'm conversational, I'm not out to hammer you, for me it's the thrill of the hunt for truth. Just as an intro, my degree is in psychology but when I got into the real world I hated it didn't have the maturity to deal with that level of problems back then, I think. For the last I've been making my living working as a programmer because that's just the kind of thinking that's native to me.

I'm a rabid bookworm, favorite reads are history and theology. I'm an amateur linguist, currently trying to pick up Arabic. On the personal side, I'm a mom with 2 kids Dad skipped out years and years ago. I like bike rides and cooking and am having a blast Christmas-shopping for the little people.

As far as beliefs go, I've looked around and studied. Btw I have a passion for other religions in the sense of recognizing the "preparatorio" in them and not misrepresenting them. I have a decent comparative religion section in my bookshelves. Unfortunately, I may have to temporarily postpone this discussion for reasons of busyness: An atheist Prof. If you would, pray that this goes well, as I will pray for you and your children. Thank you for your splendid response; I look forward to our conversation.

Guys- Thanks for writing and for the insights. I apologize for taking a couple of days to respond…life and all. First, you should know that Brian may sound like a smart guy, but he is. Doubtless there is more to the difference than these two syllogisms, but they probably give a good basic outline. First syllogism: 1.

No thought is valid if it can be fully explained as the result of irrational causes. If materialism is true, then all thoughts can be fully explained as the result of irrational causes. Therefore, if materialism is true, then no thought is valid. A thesis whose truth entails the invalidity of the thought that it is true ought to be rejected, and its denial ought to be accepted.

Therefore, materialism ought to be rejected, and its denial ought to be accepted. Second, updated syllogism: 1. No belief is rationally inferred if it can be fully explained in terms of nonrational causes. If materialism is true, then all beliefs can be fully explained in terms of nonrational causes.