Friday, 4 October 2013

Planting a Defeat

A while back, I got the following feedback on the article Planting a Tiger (I can’t help myself, so I’ve marked typos in red – I just feel so proud when I notice any typos myself rather than having others point them out to me):

Quote: neopolitan (reddit/r/atheism)

A person, on the other hand, who commences with a huge assumption and then brutally twists logic to form a disparate array of lesser assumptions into a bridge between the state of things as they are and the state one should expect if the initial huge assumption were true, is not a philosopher. He is what we refer to as an "apologist".

But both Craig and Plantinga would argue that they are seeking knowledge and understanding. They would argue that they are following the evidence where it leads and not shying away from reality. You can both be an apologist and a philosopher. It is one thing to say that they are wrong (maybe they are) but it is something completely else to say that they are deliberately twisting the truth and don't deserve the title of 'philosopher'.

The article's well written. Correct me if I'm wrong but the crux of your argument seems to be here:

Quote: neopolitan (Planting a Tiger)

Plantinga totally ignores that the scientific method takes into account the suggestion that, individually, our cognition is faulty but that this may be overcome if we don’t assume our beliefs to be true, we gather evidence to support or refute our beliefs, we have the intellectual courage to accept when evidence does refute our beliefs, we invite others to critically assess our evidence and our interpretations of that evidence where it seems to support our beliefs and we have the grace to accept that we were wrong if the evidence or interpretation is shown to be problematic.

What Plantinga tries to show is that the scientific method can't stand up to the same criteria by which it judges everything else. You said at the beginning of your article that scientists are 99.99999% sure before committing to the truth of a claim. Can scientists be 99.99999% sure that our cognitive abilities align with reality? If not, then what does that say about using science as a criterion for judging truth? If we are not 99.99999% sure that our cognitive abilities are reliable then doesn't science itself rest on an unfounded belief?

I was initially responding to a claim (by another redditor) that I had erred in bracketing the word “philosopher” with quotation marks when using that word in reference to Alvin Plantinga.  My contention, as my quote above indicates, is that Plantinga is not so much a philosopher as an apologist (and possibly theologian) despite his apparently impressive academic qualifications in philosophy.  (To address what might seem like a valid reason to call Plantinga a philosopher – and even Craig, for that matter – please see Draconic Philosophy.)

In Planting a Courted Controversy, I related what happened after I had actively sought feedback from the WLC Fan Club at the Reasonable Faith website.  In the conclusion to that article, I agreed that I had not provided a comprehensive argument against the Evolutionary Argument Against Naturalism (EAAN), which is what is being alluded to above with “If we are not 99.99999% sure that our cognitive abilities are reliable then doesn't science itself rest on an unfounded belief?”

Here then is my argument as to why the EAAN fails …


I’ll explain what the EAAN is, as best I can (generally using Plantinga’s words) and put in comments where necessary:

Step 1 – Develop the probability expression P(R|N&E)


R is the claim that our cognitive faculties are reliable,

N is metaphysical naturalism, including the claim that there is no God

E is the claim that our cognitive faculties are the product of evolution


P(R|N&E)  is the question “What is the probability of R if both N and E are true?”

Step 2 – Argue that P(R|N&E) is low

Since there is no reason to suppose that evolution unguided by God will favour reliable cognitive faculties (see Planting a Tiger for why he thinks this is the case), then P(R|N&E) is “relatively low, somewhat less than 1/2”.

Comment: This is an extraordinarily weak argument.  There is plenty of evidence to support the idea that animals with poor cognitive faculties will die out, this is particularly so if they are delicious – roasted dodo, anyone?

In reality, Plantinga’s argument falls down right here, he fails to provide a convincing argument as to why the beliefs of a human, if they were evolved, would be unlikely to be true.  His argument is so laughable that originally I didn’t think it needed more effort, but let’s continue ...

Step 3 – Argue that P(R|N&E) is inscrutable

Admit that “the argument for a low estimate for P(R|N&E) is pretty weak” and then claim that perhaps it is better to be agnostic with regard to this probability, on the grounds of it being “inscrutable; we just can’t tell what it is”.

Comment: This raises the question of why the argument was presented at all if it’s considered, even by Plantinga, as “pretty weak”.  Cynically, one could suggest that he does so in order that the “inscrutable argument” might appear less weak in comparison.  If that was the intent, it worked … by a narrow margin.

Step 4 – Argue that if P(R|N&E) is inscrutable, then P(R|N&E) is inscrutable

I’ll have to use Plantinga’s words here or it will sound like I am misrepresenting his argument (taken from his lecture notes):

Of course the argument for a low estimate of P(R/N&E) is pretty weak. In particular, our estimates of the various probabilities involved in estimating P(R/N&E) with respect to that hypothetical population (comment - a hypothetical population of creatures rather like ourselves on a planet similar to Earth … (that had) arisen by way of the selection processes endorsed by contemporary evolutionary thought as indicated in an earlier paragraph – ed.) were pretty shaky. So perhaps the right course here is simple agnosticism: that probability is inscrutable; we just can’t tell what it is. This also seems sensible.

What would then be the appropriate attitude towards R (specified to that hypothetical population)? Someone who accepts N&E and also believes that the proper attitude towards P(R/N&E) is one of agnosticism, clearly, has good reason for being agnostic about R as well.

But now suppose we again apply the same sort of reasoning to ourselves and our condition. Suppose we think N&E is true: we ourselves have evolved according to the mechanisms suggested by contemporary evolutionary theory, unguided and unorchestrated by God or anyone else. Suppose we think, furthermore, that there is no way to determine P(R/N&E) (specified to us). What would be the right attitude to take to R? Well, if we have no further information, then wouldn’t the right attitude here, just as with respect to that hypothetical population, be agnosticism, withholding belief? If this probability is inscrutable, then we have a defeater for R, just as in the case where that probability is low.

So P(R/N&E) is either low or inscrutable; and if we accept N&E, then in either case we have a defeater for R.

Now, trying to turn this into English for the rest of us ... the value of P(R|N&E) with respect to a population of evolved creatures is unknown and, according to Plantinga, unknowable (i.e. inscrutable).   If we, as evolved creatures, accept that both N and E are true, but are agnostic about P(R|N&E), as Plantinga argues we must be, then we should rightly be agnostic about R (by which Plantinga seems to mean P(R) since he refers to “this probability”).

In short, if P(R|N&E) is inscrutable and N&E is true, then P(R) is inscrutable.

Comment: My sarcastic wording of this step reflects the fact that, if N&E is true, P(R) = P(R|N&E), irrespective of what the value of that probability is – inscrutable or low or, indeed, high.

Step 5 – Argue that if P(R|N&E) is inscrutable (or low) then R has a defeater

Actually, I can’t really see how he justified this step, but I can see why he does it.

A “defeater” is a proposition which, if in the possession of a person who otherwise would have a justified true belief constituting knowledge about something, would negate the justification or the belief (but not the truth).  It’s a term from epistemology, the study of knowledge, and it relates a particularly esoteric discussion as regards to what we can “know”.

In the tripartite theory of knowledge, in order to truly know something rather than just believe something to be true:

the something in question must be true;

one must maintain a belief that that something is true; and

that belief must be justified.

If you are deluded in your belief about something then you cannot know it (for example, correctly believing that the sun is not the centre of the universe would not count as knowing if your reason for believing is that you also believe that the Earth is the centre of the universe).

Perhaps you might be in possession of a fact which you do not accept or do not understand, for example the fact that the Bertrand Paradox has a unique resolution such that p=0.5, you can’t really say that you know this if you don’t believe it.  (If you believe this fact to be true, but you don’t understand it, you might still know it if, for example, you had been informed by an expert in the field.  So long as it is true, of course.)

Finally, you can’t know something that is not true.

I suspect that there’s an element of equivocation and conflation involved here.  Plantinga talks about R as if it means:

the claim that our cognitive faculties are reliable, **AND**

the probability that our cognitive faculties are reliable, **AND**

the knowledge that our cognitive faculties are reliable, **AND**

the fact that our cognitive faculties are reliable

This is cheating on a major scale.

Step 6 – The Grand Finale

If you have a defeater for R, then you have a defeater for any belief you hold, including the belief that N&E is true.  Therefore it is irrational to hold the belief that N&E is true.

That’s it.  Well, he does go into a little pre-emptive defence against defeater-defeaters, but that’s largely irrelevant since you’d have to agree with Plantinga’s arrival at Step 6 and still want to hold onto N&E.  That would mean that you’d have to agree with Step 5 (and maybe Step 2) and you wouldn’t do that unless you were already presupposing the whole outcome with respect to N&E.

Let us look at Step 5 a bit more closely.

Plantinga is arguing that if we don’t know how probable it is that our cognitive faculties are reliable then it is probable that our cognitive faculties are unreliable.  Presumably, therefore, the only way that our cognitive faculties could be reliable would be for us to know that it is probable that our cognitive faculties are reliable.  But we’d only know that if they were reliable, otherwise we couldn’t know anything.

What Plantinga seems to be supposing here is some sort of bizarre bootstrapping – if you know that your cognitive faculties are reliable, then they are, and you know they are because those faculties are reliable, making your belief both true and justified.  However, if you are in doubt about the reliability of your cognitive faculties, they are unreliable by default, you know nothing and everything you believe is suspect.

This is, of course, nonsense.

As I have said elsewhere:

All (Plantinga) manages to do … is show that if naturalism and evolution are true, then we cannot know with 100% certainty that naturalism and evolution are true.  In other words, if naturalism and evolution are true, the scientific fact of naturalism and evolution is precisely the same as any other scientific fact – (because) we don’t know anything to be true with 100% certainty.

(There’s an extremely remote, non-zero chance that The Matrix was actually an ironic mockumentary screened by our mechanical overlords to taunt us and we are plugged into vats precisely as shown in what is portrayed to us as “fiction”.  This extremely unlikely possibility chips away from any otherwise perfect certainty we might have had about our world.  Scientists will think you are some sort of batty philosopher if you raise this argument, but eventually will concede that they cannot know that we aren’t in vats.)

What rational people will do is assume that the world is as it appears to be until illusions can be shown to exist.  As we detect illusions, we try to understand them so that we can account for them in our theories.  Rational people won’t deny that our cognitive faculties are limited, and prone to failure.  Nor will they assume that because those faculties are limited, and prone to failure, that they are completely useless.

And they won’t hang onto illusions just because they are comforting.

Now that I’ve explained, as best I can, the EAAN, I’d like to introduce the EAAT, which is the EAAN Argument Against Theism, or to give it its full glory …

“Evolutionary Argument Against Naturalism” Argument Against Theism Version 1

Step 1 – Do the whole EAAN thing

Step 2 – Point out that if N&E is true, then it is irrational to believe anything Plantinga has to say, given that he is just an evolved form of tiger food

“Evolutionary Argument Against Naturalism” Argument Against Theism Version 2

Step 1 – Do the whole EAAN thing

Step 2 – Consider the following:

·         If N&E is true then, irrespective of whether or not you believe that N&E is true, then it is quite likely that you will hold beliefs that are incorrect

·         If you continually challenge all of your beliefs, then those beliefs which consistently survive challenge will be more likely to be true

·         If a belief which fails a challenge is modified and then, as a consequence of being modified, consistently survives challenge, then that modified belief is more likely to be true

·         If N&E is continually challenged and consistently survives, then it is likely to be true

·         If N&E is challenged and fails, then is modified and the modified variant, N&E*, consistently survives challenge, then it is likely to be true

·         If another belief, say theism (T), is continually challenged and consistently fails, then it is unlikely to be true

·         If a belief is unchallenged and the holders of that belief are not willing to accept challenge, then the probability of that belief being true is inscrutable (you might want to follow Plantinga’s own argument here to reach the conclusion that holding such a belief is irrational)

From all this, we can conclude that:

·         P(R|N&E|S) is high when S is high (where S is the extent to which naturalism and evolution consistently survive challenges), and

·         P(R|S) is high when S is high (because the reliability of our cognitive faculties is also continually challenged)

The fact that N&E have been modified throughout the years, particularly the E component, is an indication that N&E is more likely to be true.  As a consequence, it is entirely rational to believe both that R is true and N&E is true.

On the other hand, however:

·         P(T|F) is low when F is high (where F is the extent to which theism fails being challenged), and

·         P(T|A) is low when A is high (where A is the extent to which theism avoids being challenged – see also being an infidel and apostasy).

Unlike with many other sorts of beliefs, there is great resistance to variations to T, therefore there is no T* as such (where T* is an improved version of theism) and T has no avenue by which to evolve towards a truth statement.

In other words, yes, I agree with Plantinga: many beliefs held by evolved creatures are likely to wrong, especially if they are untreated.  Even some of the smartest humans that ever lived used to believe such things as:

·         everything is a combination of up to four elements

·         phlogiston is a substance that escapes matter when it burns

·         there is an aether that conducts light

·         those enormous bones unearthed by mining and erosion are the bones of dragons

·         narwhal horns belonged to unicorns

These people were wrong.

Who knows, maybe string theory is a load of old cobbler’s.  But the point is, even if this is the case, scientists are actively encouraged to investigate string theory, to uncover how the theory is wrong and which associated beliefs are wrong.  Scientists working in the field will then, collectively, attempt to come up with something that is slightly better, but almost certainly also wrong in its own special way – and the process will continue.

This sounds like a terrible system, and perhaps it is.  A far worse system, however, is to cling unquestioningly to a demonstrably false belief which requires you to brutally corrupt logic in order to divert attention from the wealth of evidence against that belief.

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