Saturday, August 26, 2017

Skeptical Threats and Best Explanations


Let me explain the difference between a Skeptical Threat argument and a Best Explanation Argument.  If I were giving an STA I would be saying that a non-naturalist position allows you to refute the skeptic but a naturalist position does not. I don’t like this kind of argument because I am not sure you can refute the skeptic in any event. In fact when I first read Plantinga’s EAAN I thought his argument was a skeptical threat argument.
A BEA says that both we and our opponents depend upon the existence of certain mental states. In particular, we believe some things because the evidence is good. Let’s take a statement that is typical of atheists:
Next time somebody tells you something that sounds important, think to yourself: ‘Is this the kind of thing that people probably know because of evidence? Or is it the kind of thing that people only believe because of tradition, authority or revelation?’ And, next time somebody tells you that something is true, why not say to them: ‘What kind of evidence is there for that?’ And if they can’t give you a good answer, I hope you’ll think very carefully before you believe a word they say. –Dawkins
http://jdstone.org/cr/files/richard-dawkins-letter-to-his-10-year-old-daughter.html
Here he presupposes that some people, unlike those religious people who believe based on tradition, authority, and revelation, some people believe things based on evidence. Every atheist I know is going to accept as an agreed upon datum that some people form beliefs based on the evidence. If Dawkins says he believes in evolution by natural selection based on the evidence, he is implying that he believes because the evidence for it is present and wouldn’t believe it if it were absent. Hence coming believe something based on evidence is something both sides are going to have to explain, not explain away. On pp. 64-65 of CSLDI I argue that statements that a belief is based on evidence entails claims about how those beliefs were caused. The existence of mental causation, the fact of someone coming to believe something because the evidence for it is good, is something both sides are going to have to be able to explain.
Lewis’s theistic solution to the problem is this:

On these terms the Theist's position must be a chimera nearly as outrageous as the Naturalist's. (Nearly, not quite; it abstains from the crowning audacity of a huge negative). But the Theist need not, and does not, grant these terms. He is not committed to the view that reason is a comparatively recent development moulded by a process of selection which can select only the biologically useful. For him, reason--the reason of God--is older than Nature, and from it the orderliness of Nature, which alone enables us to know her, is derived. For him, the human mind in the act of knowing is illuminated by the Divine reason. It is set free, in the measure required, from the huge nexus of non-rational causation; free from this to be determined by the truth known.  And the preliminary processes within Nature which led up to this liberation, if there were any, were designed to do so.

http://www.philosophy.uncc.edu/mleldrid/intro/csl3.html
Accusing Lewis’s argument of the genetic fallacy seems to be a mistake. The genetic fallacy occurs when I say a belief has to be wrong based on how it was produced. Not every belief has to be rationally inferred in order to be justified. But a belief which is based on evidence, (and you atheists insist that you have some of those), needs to have evidence amongst its causes. But if the physical world is causally closed and mechanistic, then the use of evidence, which involves the logical relationship between the evidence and the evidenced proposition, never happens.
So, this is how I would rebut the two strategies you offer the naturalist. The high price of naturalism, or part of it, is that you have to give up science as a means to truth, and give up the claim that you believe anything based on evidence. I suppose there are some naturalists out there willing to pay that price. I don’t think I’ve met one, however.




21 comments:

entirelyuseless said...

Again, I think you are confused about kinds of causality.

The light that reflects off an apple is evidence of the presence of an apple. That light is part of the physical cause of my belief that an apple is present. So my belief can have physical causes, and still be caused by evidence.

Hal said...

Victor,
"I argue that statements that a belief is based on evidence entails claims about how those beliefs were caused. The existence of mental causation, the fact of someone coming to believe something because the evidence for it is good, is something both sides are going to have to be able to explain."

Nice illustration of your assumption of mental causation.

Irregardless of whether one is a theist or an atheist, if asked to explain why they think the evidence for it is good they they simply give it. We can do that because we are language users. Humans have the capacity to reason and to express those reasons in language.

You are confusing the vehicle with its power. What enables a person to have the capacity to reason does not have to be reason itself.

"He is not committed to the view that reason is a comparatively recent development moulded by a process of selection which can select only the biologically useful."

Irrelevant. Even a theist can reasonably believe that their God used evolution to produce language using animals capable of reasoning.

Although I am an atheist, the philosopher who has had the greatest influence on me, Wittgenstein, was a theist. He never tried to use God or supernatural forces to understand and explain human behavior in his philosophy.

Hal said...

An example illustrating the difference between a vehicle and its power:

When someone sees you have a watch and asks you for the correct time they are not asking you to explain how the inner workings of the watch enable it to give the correct time. They simply want to know the time.


(Sorry for all the deleted posts. I really need to start reading my own posts more carefully before posting them!)

Stardusty Psyche said...

" But if the physical world is causally closed and mechanistic, then the use of evidence, which involves the logical relationship between the evidence and the evidenced proposition, never happens."
--Non sequitur. Why?

The difficulty in rebutting that sort of statement is that it is so baseless that one has a hard time identifying the specific erroneous basis to address.

Our brains process information applying various transforms, including logical relationships to sensed evidence. From that we take actions. The quoted statement seems oblivious to these rather obvious facts.

Hal said...

"Our brains process information applying various transforms, including logical relationships to sensed evidence. "

What criteria are you using to identify such processing?

Victor Reppert said...

Brains are not objects. They are collections of objects whose activities are determined, insofar as they are determined, by the laws of physics and prior facts. So, once again I say "Interesting fellow Mr. Brain. Remarkable what he can do." But to be a consistent materialist, you cannot turn a brain into a soul, or a person. It is what it is.

Stardusty Psyche said...

Victor Reppert said.. August 27, 2017 12:53 PM.

" Brains are not objects. They are collections of objects"
--Every object above the level of quarks, electrons, and neutrinos is a collection of objects, so this is not a valid distinction.

" whose activities are determined, insofar as they are determined, by the laws of physics and prior facts."
--I would quibble about "laws" and say "principles, but, OK.

" So, once again I say "Interesting fellow Mr. Brain. Remarkable what he can do." But to be a consistent materialist, you cannot turn a brain into a soul,"
--Hence, the non-existence of the soul.

" or a person."
--Ahhh, now there is a rub... On materialism there is no conflict between our sense of personhood and a mechanistic accounting for all we are and all we perceive.

" It is what it is."
--Indeed, it is a highly complex sensing, processing, motor control multiprocessing, multinetworked mechanism. In higher animals the sense/process/act function is turned on itself forming self-awareness.

Victor Reppert said...

But you cannot talk about the brain in terms that imply that it is a soul, and then use that to show that there isn't a soul.

Are there things above the level of physics? Real entities, with real essences, not just groups that a mind calls entities?

Hal said...

Victor,
Brains are not objects.

Not sure what your point is. A brain is certainly an organ, a part of a body. Are you claiming brains don't actually exist?

A mind is not an object. A mind is not a thing at all. The word "mind" is a façon de parler. We say a human has a mind because humans display a particular range of active and passive powers of intellect and will. It is the human being who thinks, acts on his thoughts and express his thoughts in language.
It makes no sense to attribute those powers to the brain nor to the mind.

I'm sympathetic toward your critique of reductive materialism. However, the falsity of that metaphysical position does not entail the truth of yours.

Victor Reppert said...

I didn't say that it did. There are some alternatives as to where the nonreductive materialist can go in developing their position. But I think there are problems with each way of developing it.

Hal said...

Ok. Thanks for the clarification.

David Brightly said...

I looked at the Lewis reference. On page [27] he says,

The act of knowing has no doubt various conditions, without which it could not occur: attention, and the states of will and health which this presupposes. But its positive character must be determined by the truth it knows. If it were totally explicable from other sources it would cease to be knowledge, just as (to use the sensory parallel) the ringing in my ears ceases to be what we mean by 'hearing' if it can be fully explained from causes other than a noise in the outer world--such as, say, the tinnitus produced by a bad cold. If what seems an act of knowledge is partially explicable from other sources, then the knowing (properly so called) in it is just what they leave over, just what demands, for its explanation, the thing known, as real hearing is what is left after you have discounted the tinnitus. Any thing which professes to explain our reasoning fully without introducing an act of knowing thus solely determined by what is known, is really a theory that there is no reasoning.

Later, page [32], he says,

Inference itself is on trial: that is, the Naturalist has given an account of what we thought to be our inferences which suggests that they are not real insights at all.

Lewis seems to be suggesting that there are real inferences and 'fake' inferences. It's as if the means by which the concluding proposition is reached from the premises influences the 'genuineness' of the conclusion. Is that fair? But how can a proposition have a 'genuineness'? There are true and false propositions but not real and fake ones. It seems to me that it doesn't matter how the concluding proposition is arrived at---be it by neurons, transistors, or rational soul---as long as it and the premises match with a valid rule of inference.

William said...

David,

I think you need to go one level "meta" from where your post seems to imply you are to understand the argument better. Lewis means the logical deduction activity itself as an 'inference' not the proposition that the logical machinery is using.

To paraphrase the last quote:
"
[Logical]Inference itself is on trial: that is, the Naturalist has given an account of what we thought to be our [logic] which suggests that [it need not be correct logic] at all.
"

In other words, Lewis is suggesting that with pure materialism, all reasoning is motivated reasoning, which makes it all potentially suspect.

I think this is similar to Kant's assertion that categorical norms cannot be reduced to the natural facts they are about, because this would limit their level of application and thus make them non categorical.


William said...

One thing more: by motivated reasoning I would not mean the type where the premises are tailored for the desired conclusion but the logic is correct, but the type where the logic is faulty but the conclusion is what is needed.

David Brightly said...

Hello William, Yes, Lewis uses a number of terms---'act of knowing', 'inference', 'insight'---and it wasn't clear to me whether he was referring to a conclusion or the process of reaching it. Let's suppose the latter. A similar line of thought then occurs: Lewis is suggesting that there can be real inferential processes and fake inferential processes. Again, I reject this, noting that the only distinctions we make are between valid and invalid inferential processes. It seems to me that it doesn't matter how the inferential process is achieved---be it by neurons, transistors, or rational soul---as long as the conclusion and the premises match with a valid rule of inference. The test of a valid inferential process is that it should be truth-preserving---it mustn't deliver a false conclusion when the premises are true. That's the only requirement, and it doesn't matter how it's achieved. It so turns out that the structure of our language is such that valid inferences can be made mechanically. So the materialist is in with a chance, as it were.

Hal said...

David,

I agree with your analysis. The only criteria is that one be able to put forth a valid argument. Whatever goes on in the mind that enables a person to express that argument is irrelevant.

Lewis had a brilliant mind. I consider him to be one of the most astute literary critics of the 20th century, but I don't think his philosophical analysis fares so well.


William said...

Logical validity and a valid use of language for logic requires a knowledge of logical rules, so the Lewis argument can be re-stated with "valid" instead of "logic" above, and still works: Lewis might say that with only material objects allowed to work with, we have undercut our ability to know what is valid about our language usage. "Valid" is not a physical property.

David Brightly said...

I agree that 'valid' does not denote a physical property. Movements of chess pieces are classed as valid or invalid in accordance with the rules of chess. Likewise there are valid and invalid 'moves' in the 'game' of inferential logic, where a 'move' is the addition of a further proposition to a set of accepted propositions. In a game of chess with physical board and pieces the abstract attribute 'valid' is instantiated in physical movements of the pieces. The same can be said for changes in physical representations of propositions, if this is possible.

Victor Reppert said...

A mechanical system can perform a valid inference if there is an interpreter in the background providing the meanings. The intentionality of a mechanistic system is derived intentionality, based on content provided by intelligent design. If we know the meanings we can mechanize our reasoning.

Hal said...

I don't think I understand how you are using the word "intentionality" in this situation.

A human can perform a valid inference if they understand the terms they are using and know the rules of logic. What does intentionality have to do with that?

David Brightly said...

Are you saying, Victor, that meaning is necessary for valid inference to occur? Modus ponens, defined as the rule of inference 'given the sentence p and the sentence p-->q infer the sentence q' is independent of p and q, so their meanings cannot come into it, surely?