The Evolutionary Argument Against Naturalism

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Why? On the face of it, it seems to me completely reasonable to assume that we could trust a mind that was designed, and distrust one that was evolved by chance and natural selection.

First, brains don’t function perfectly, and we tend to muddle through things like logic, epistemology, and recently empiricism, which took thousands of years of social/historical thinking to formalize.

I disagree that Natural selection would not be able to produce brains that have basic logical qualities.

Natural selection would tend towards brains that enable survival in a universe where there are distinct patterns. Being able to decipher these patterns, act on them, and even think abstractly to plan for patterns, in a goal oriented way, is a huge selective advantage.

Secondly:

A designer doesn’t equate to a competent designer, that is just the convenient assumption attached to religions like Christianity (God is perfect). The problem is that we would not know how the designer appeared, since If the designer appeared by chance, or natural selection it would be inherently untrustworthy under the same argument...

 

[Osiris]

[/b]
Why? On the face of it, it seems to me completely reasonable to assume that we could trust a mind that was designed, and distrust one that was evolved by chance and natural selection.

Not really... it is still illogical.

Let me break it down to show you the errors in this whole OP:

Life was either designed, or it wasn't.

If you can trust a designed brain, but you can't trust an evolved one then :

(1) If God designed life, then he designed monkey's as well. Next time you are sick with a life-threating disease, anyne who adheres to Plantingas belief should go visit a monkey for the cure... since a monkey would have been designed as well. But if you can't trust a monkey's brain who was "designed" , then this whole
argument of "trusting a designed brain" has no basis.

(2) If evolution is true, and humans came about by chance and circumstance... then, why do people go to doctors? I am pretty sure CS Lewis and Plantingas must have gone at least once. If they did, that would make them hypocrites.... because, they would be putting their trustu on the doctor's brain.

If you read Plantinga's argument, you will see the answer to this question. If you want to respond to the argument, you could at least read it.

Judging from the premises... arguments with flawed premises aren't really much of arguments.

btw, If you read the post you replied... i was merely agreeing with RecoveringP. regarding CS Lewis as an author.

It was Charles Darwin who spoke about the monkey, not Lewis.

I didn't say CS Lewis did... using sources like quoting Authority figures to lower the credibility of something is poisoning the well.

The only mistake though, is that I thought it was CS Lewis who used that quote... but it was Plantingas who was committing such fallacy.

 

[DrkSdBls]

We humans are prone to think that rationality and logic are not subjective attributes of our own reasoning, but are in fact universal laws - laws that even God, if He exists, is subject to.

Correct. We do tend to believe that. But as any person with any strong convictions will tell you, what is logical to one isn't necessarily Rational to another.

In reality, there are no "Laws of Logic." Such concepts are not an "Exact Science." Like I said before, there's only a certain Standard by which we accept as defining Logic and Reason so as we all can think on the same level in the attempt to share our points of view. It is this Standard of Logic and Reason that we employ when we exercise intellectual ideas and Practices and this Standard will continuously change as our understanding continues to grow.

Thus, it's Entirely subjective!

Your argument sounds a bit confused. I'm not sure why you think that a designed mind would use the same reason and logic as an evolved mind.

No, you've merely misread what I've said.

A Rose by any other Name is still a Rose. Or, rather:
A Rose created by Hand would still smell as sweet as a Rose Grown in a Garden, if they are the same rose.

I didn't say that both a Created mind and an Evolved mind would necessarily be the same thing. I said, that our mind, whether it was Evolve or Created, is still the same mind which we are discussing and regardless of it's origin is still only capable of the same level of reason and logic as it is limited to. Anything our minds are cabable of is exactly the standard by which we measure our Minds, regardless of whether they be Evolved or Created.

The former could be designed to understand the true laws of logic, while the latter could (and probably would) generate false beliefs. You state earlier that Logic and Reason are subjective concepts. Here you say that a designed mind and an evolved mind would need to be the same. Which is it?

By your reasoning, the fact that we often generate false beliefs proves that our mind must be Evolved, since only an evolved mind is flawed enough to do so.

There is no reason for you to say that a Created Mind is capable of understanding Complex Logic while an Evolved is not because you only have one mind from which to draw your conclusions.

If that mind was Created, what gives you the impression that it is more capable of complex Logical Processes then a Evolved Mind when you have not a Evolved mind for which to compare? And Vice Versa for a Evolved mind.

My point is that, until you can show me both a Created mind and an Evolved mind to compare and contrast, you can't make such an assertion. Until then, all we have is our mind, regardless of it's origins, and if it Flawed then it's flawed.

So, it comes down to, not whether we can trust a Designed Mind over an Evolved Mind, but rather can we trust our Mind as it is, even with it's obvious flaws. The Answer is: What choice do we have?

 

[KCfromNC]

Plantinga argues against this premise. In fact, Plantina also argues that true belief is not even necessary. What is necessary (if beliefs are causally related to behaviour) is that they move you in the correct way. And a belief does not have to be true, or even close to true, in order to do that. Stating the above is not sufficient to demonstrate it. I already know that you believe the above to be true - what you need to do is explain why you think Plantinga is wrong.

The odds of a naturalistic evolution producing a mind which has beliefs which are consistently "incorrect" yet move you in a "correct" way are so extremely low to be ignored. Think about it - you'd have to produce a belief system that was wrong, yet consistently wrong in just the right way to always produce correct behavior when relating to your environment. This would be way harder than just dealing with the real world by producing true beliefs. At this point instead of actually doing math, I'm going to take the approach of the original argument and just assert that it's therefore impossible that naturalism could produce wrong-but-consistent beliefs and therefore conclude that these beliefs are in fact true. In the nature of the burden of proof shifting traditional to these sorts of transcendental arguments for gods, feel free to demonstrate why you think this is wrong.

Incidentally, there seems to be a lot of neo-platonic claptrap about some idealized level of true beliefs that exist outside of the natural world in these arguments. On what basis do you conclude that a belief is false if it helps produce behavior that aids in understanding the natural world? I think there's some equivocation in the word "truth" here, and it doesn't seem fair to condemn naturalism because it doesn't account for the assumed "truths" of the supernatural.

 

[Apollo Rhetor]

Just a quick response now to one post, then a response to others if I have time:

The odds of a naturalistic evolution producing a mind which has beliefs which are consistently "incorrect" yet move you in a "correct" way are so extremely low to be ignored. Think about it - you'd have to produce a belief system that was wrong, yet consistently wrong in just the right way to always produce correct behavior when relating to your environment.

There's not much point discussing Plantinga's argument if you're not willing to read it. This is only part of what he discusses, and you'll have a much better idea of the breadth of his coverage once read.

 

[KCfromNC]

There's not much point discussing Plantinga's argument if you're not willing to read it. This is only part of what he discusses, and you'll have a much better idea of the breadth of his coverage once read.

I was addressing a particular point you made. It's really not fair to make me guess what other arguments you'd like to make to back up your point. Feel free to add more detail if you've omitted relevant info in the post I responded to. Or you could actually point out where my thinking is wrong. Since you've read the original work it should be easy to do.

But if the best you can do is claim that there might be a response to my objection somewhere in the original work, I'll agree that there's not much point in "discussing" this.

 

[Pesto]

C. S. Lewis was a hack, and that you think he was so smart indicates your own lack of education.

http://www.christianforums.com/showt...3#post34352073

 

[Loudmouth]

There's not much point discussing Plantinga's argument if you're not willing to read it.

There's not much point in discussing Plantinga's argument if you are unwilling to discuss it as well. This is a discussion forum, not a suggested reading forum. If you have read it and understand it you should be willing to summarize it here.

 

[Apollo Rhetor]

There's not much point in discussing Plantinga's argument if you are unwilling to discuss it as well. This is a discussion forum, not a suggested reading forum. If you have read it and understand it you should be willing to summarize it here.

Excuse me? On what plane of existence does this make sense? It is quite common to expect that if you're joining discussion on an article or paper, that you will read the paper in question to discuss it. On Slashdot, a common response is RTFA, an expectation that if you want to comment, you'll at least take the time to read the story as it appeared.

Why should I waste my time summarising something that's there for you to read already? I'm quite happy to discuss Plantinga - but it will save time for both of us if you read it first.

Now if you don't have enough interest to read Plantinga's argument, then why would you want to discuss it? At best you'll just defeat someone's repetition of Plantinga's argument, rather than seeing for yourself if your objections are warranted against the argument as its main proponent presents it.

 

[KCfromNC]

Excuse me? On what plane of existence does this make sense? It is quite common to expect that if you're joining discussion on an article or paper, that you will read the paper in question to discuss it. On Slashdot, a common response is RTFA, an expectation that if you want to comment, you'll at least take the time to read the story as it appeared.

Why should I waste my time summarising something that's there for you to read already? I'm quite happy to discuss Plantinga - but it will save time for both of us if you read it first.

Now if you don't have enough interest to read Plantinga's argument, then why would you want to discuss it? At best you'll just defeat someone's repetition of Plantinga's argument, rather than seeing for yourself if your objections are warranted against the argument as its main proponent presents it.

To be fair to the people responding here, this is not exactly the first time we've seen yet another variation of the argument from ignorance. In this case, the argument is "we don't know how beliefs are related to behavior, so naturalism can't be true". Sure, it's dressed up in lots of impressive looking probability and words like "true belief, "warrant" and "defeater", but it's the same god of the gaps we've seen here before many times. ID's do it, the TAG from presuppers use it, the big bang deniers use it, and it's equally weak in all cases. Based on the presentation here by it's supporters, I don't see any reason to look at this yet another time (all the word salad gets tedious).

I also can't help but notice that you just wrote 3 paragraphs complaining that you can't take the time to respond to anyone's questions. It seems to me that if our objections were amateurish, it'd be quicker to use those 3 paragraphs to show that we're off base and this particular argument is different. Instead, it just looks like you're trying to change the subject.

It's not like the objections made in this thread are significantly different from the ones raised by professional philosophers. See, for example, Fitelson and Sober's paper for a more rigorous treatment of many of the arguments here, if you'd prefer to just trade sources instead of discussing.

 

[Apollo Rhetor]

To be fair to the people responding here, this is not exactly the first time we've seen yet another variation of the argument from ignorance. In this case, the argument is "we don't know how beliefs are related to behavior, so naturalism can't be true". Sure, it's dressed up in lots of impressive looking probability and words like "true belief, "warrant" and "defeater", but it's the same god of the gaps we've seen here before many times. ID's do it, the TAG from presuppers use it, the big bang deniers use it, and it's equally weak in all cases. Based on the presentation here by it's supporters, I don't see any reason to look at this yet another time (all the word salad gets tedious).

Two points on this:
1. Plantinga's argument is not an argument from ignorance. Plantinga lists all the possible ways in which belief can relate to behaviour (rather than just saying we don't know how), and then examines the probability that our cognitive faculties will form close approximations to truths in beliefs in each of those scenarios. That's more than just throwing up our arms and saying "we don't know!"

2. I think you're giving entirely too little credit and respect to Plantinga as a philosopher, and the argument he presents. Saying that it's just the same old argument "dressed up" is an attempt to dismiss it as something else, without actually analysing it. If you think it's the same, then explain why. Right now it just sounds like you're ready to comment on an argument you haven't read. You're certainly entitled to your opinion that it's the same as everything else - but it's absurd to try and make me look like I'm unreasonable for expecting people to read what they're quick to have an opinion about.

I also can't help but notice that you just wrote 3 paragraphs complaining that you can't take the time to respond to anyone's questions. It seems to me that if our objections were amateurish, it'd be quicker to use those 3 paragraphs to show that we're off base and this particular argument is different. Instead, it just looks like you're trying to change the subject.

If I can spend three paragraphs convincing people to read the article, and save myself fifteen paragraphs, and move therefore right into the meat of the argument then it's all good (though it seems I've failed). I don't want to spend my time repeating what Plantinga wrote. I want to discuss the content and arguments he present. Let's skip the elementaries.

It's not like the objections made in this thread are significantly different from the ones raised by professional philosophers. See, for example, Fitelson and Sober's paper for a more rigorous treatment of many of the arguments here, if you'd prefer to just trade sources instead of discussing.

If you have a link to this paper, I'd like to read it, or a reference to where in a journal I might find it.

Anyway, I'm not a school teacher for you guys. The argument's right there in Plantinga's paper. If you're interested in analysing and criticising it, I'm happy to discuss it. If not, then I've wasted my time.

 

[KCfromNC]

Two points on this:
1. Plantinga's argument is not an argument from ignorance. Plantinga lists all the possible ways in which belief can relate to behaviour (rather than just saying we don't know how), and then examines the probability that our cognitive faculties will form close approximations to truths in beliefs in each of those scenarios. That's more than just throwing up our arms and saying "we don't know!"

Considering that this sort of thing is still an open question in the cognitive sciences, I'd call it premature to say that Plantinga has listed all of the ways that are possible.

But my objection was more towards playing fast and loose with the probability (hence my original objection). Since we really don't know how beliefs and behavior are related neurologically, it's a form of argument from ignorance to try to draw conclusions after assuming the relative probabilities of those various assumed mechanisms.

2. I think you're giving entirely too little credit and respect to Plantinga as a philosopher, and the argument he presents. Saying that it's just the same old argument "dressed up" is an attempt to dismiss it as something else, without actually analysing it. If you think it's the same, then explain why. Right now it just sounds like you're ready to comment on an argument you haven't read. You're certainly entitled to your opinion that it's the same as everything else - but it's absurd to try and make me look like I'm unreasonable for expecting people to read what they're quick to have an opinion about.

As I said before, I'm responding to what you wrote. There's no point going into detail if the argument fails on basic points, such as the assertion that P(R|E&N) is low - this is what I tried unsuccessfully to get you to explore with my original response.

And yes, I find philosophy similar to early attempts at science, where people thought that they could derive information about the real world by making various assumptions and using deductive logic. That didn't get them very far then, and it's no more useful now. It's an interesting diversion from reality, but not all that applicable to the real world.

In my view, the argument does share a lot of similarities to the TAG in the unreasonable assumptions department : that there are good chances god exists, the nature of god "surprisingly" matching up with the attributes of the Christian god, the chances of understanding anything given naturalism being true are low, and so on. Given that I've wasted enough time on that argument, I'm not enamored with the idea of reading another 60 pages of similar arguments until I can see that it can stand up to even basic questions. So far, no one's given me any reason to believe that it can, and instead it's just more of the same from modern Christian apologists.

If I can spend three paragraphs convincing people to read the article, and save myself fifteen paragraphs, and move therefore right into the meat of the argument then it's all good (though it seems I've failed). I don't want to spend my time repeating what Plantinga wrote. I want to discuss the content and arguments he present. Let's skip the elementaries.

Can point me to the place in the the article where Plantinga shows the actual real numbers, given that evolution occurred, for

1. the probability that both true beliefs and successful behavior will happen as a consequence of some natural process of the brain
2. the probability that true beliefs cause successful behavior
3. the probability that false beliefs cause successful behavior
4. the probability that true beliefs cause unsuccessful behavior
5. the probability that false beliefs cause unsuccessful behavior

I didn't see these numbers in a quick scan through the article but I might have missed something. Considering that you said that he explored every possible way in which belief can relate to behavior, all of these should be in there.

If you have a link to this paper, I'd like to read it, or a reference to where in a journal I might find it.

Anyway, I'm not a school teacher for you guys. The argument's right there in Plantinga's paper. If you're interested in analysing and criticising it, I'm happy to discuss it. If not, then I've wasted my time.

Apparently I can't post links, but a google search using "Fitelson and Sober" will point you to the Wikipedia page for the Evolutionary Argument Against Naturalism", and their paper is footnote 11. It covers in more detail most of the objections made in this thread (and I assume that these guys have read the paper in detail, so no fair claiming that they don't know what the argument is), as well as a few others showing contradictions and errors in Plantinga's use of probability (hence my asking for actual numbers instead of vague assertions).

 

[Apollo Rhetor]

Considering that this sort of thing is still an open question in the cognitive sciences, I'd call it premature to say that Plantinga has listed all of the ways that are possible.

Having read the options Plantinga lists, I'm not sure your reasoning is valid. I would consider his list to be exhaustive, and would be interested to know where you think there might be holes.

But my objection was more towards playing fast and loose with the probability (hence my original objection). Since we really don't know how beliefs and behavior are related neurologically, it's a form of argument from ignorance to try to draw conclusions after assuming the relative probabilities of those various assumed mechanisms.

I'm not following your reasoning as to why you think this is the case. How is this an argument from ignorance if all possible ways in which behaviour and beliefs are explored?

As I said before, I'm responding to what you wrote. There's no point going into detail if the argument fails on basic points, such as the assertion that P(R|E&N) is low - this is what I tried unsuccessfully to get you to explore with my original response.

This is precisely what Plantinga's paper discusses. Why do I need to repeat what's there? You're wanting to discuss it with me, and have me present the argument, but you don't think it's worth wasting your time when Plantinga presents it? How is the time you spend with me any more valuable than that you spend with Plantinga?

And yes, I find philosophy similar to early attempts at science, where people thought that they could derive information about the real world by making various assumptions and using deductive logic. That didn't get them very far then, and it's no more useful now. It's an interesting diversion from reality, but not all that applicable to the real world.

This viewpoint of yours is by no means universally accepted. It has a number of interesting consequences, and deserves a thread on its own. For example:
* What then do you think of deductive reasoning in science from empirical evidence? Or do you think that is worthless as well? (Eg. PE=mgh for all falling objects on earth. This rock is falling. Therefore, its PE = mgh)
* What do you think of deductive reason that led to hypotheses to be tested, and turned out confirmed precisely because of the deductive argument initially presented?
* What about the deductive reasoning we do every day of our life? (Today is Sunday. The library is closed Sundays. Therefore, the library is closed today). Do you give a special status to some forms of deductive reasoning, but reject others? What makes you think some have greater value than others? Surely if the premises are sound, and the argument valid, we should give it consideration no matter what the conclusion.
* Do you think empirical evidence is the only evidence worth considering? If so, how can you empirically prove that statement without question begging? Surely the a priori acceptance of deductive reasoning is needed to give empiricism a firm foundation

In my view, the argument does share a lot of similarities to the TAG in the unreasonable assumptions department

What is TAG?

Can point me to the place in the the article where Plantinga shows the actual real numbers, given that evolution occurred, for
...
I didn't see these numbers in a quick scan through the article but I might have missed something. Considering that you said that he explored every possible way in which belief can relate to behavior, all of these should be in there.

What makes you think that Plantinga provides exact numbers, or even needs to? I think you're missing the point here. Either that, or you *know* that he doesn't provide numbers, and you want me to admit it so you can point out "Aha! Another weakness of the theist's argument!", all the while ignoring the fact that exact numbers are not needed. Asking for something that's not needed is a clever tactic, but it's just a distraction from the argument at hand.

For example, imagine I make the statement, "it is highly probable that any person will accept the jackpot when they win in a lottery". Do I need to give an exact probability to make my statement? No. It is sufficient for me to present reasons explaining why the probability is high. You can't say my argument is false because I can't tell you if the probability is 0.95 or 0.97. After all, I've demonstrated that it is >> 0.5, and that's sufficient.

That is exactly the same with Plantinga's argument. For him to draw a conclusion, he needs to give reasons why a given probability is >>0.5, <<0.5, or ~= 0.5. That is more than sufficient to come up with a probability for the conclusion. Does he provide this in his paper? Yes he does. Exact numbers are not needed, nor even possible to provide. But values in a range large enough to draw an inference are possible, and in fact provided.

(and I assume that these guys have read the paper in detail, so no fair claiming that they don't know what the argument is)

Nice of you to pre-empt an argument I wouldn't make. It's quite clear in their paper that they've read Plantinga's essay.

Found the paper, and will read in more detail soon.

 

[Electric Skeptic]

I've seen Plantinga's argument before, and it fails dismally. He simply makes the assertion, while offering nothing to support it, that it is unlikely that given naturalistic evolution, our brains would have evolved to give us an accurate picture of the world. This assertion is, in fact, false, and obviously so. Our brains evolved to aid our survival; the most obvious way to do so is to give us an accurate picture of the world. The probability that our brains evolved to give us an INaccurate picture of the world which nevertheless enabled us to survive will is sufficiently small as to be non-existent.

Big disappointment from Plantinga.

 

[KCfromNC]

Having read the options Plantinga lists, I'm not sure your reasoning is valid. I would consider his list to be exhaustive, and would be interested to know where you think there might be holes.

Listing broad categories is not the same as exploring all of the possible options.

I'm not following your reasoning as to why you think this is the case. How is this an argument from ignorance if all possible ways in which behaviour and beliefs are explored?

Because the argument rests not on listing all of the possible ways that beliefs and behaviors interact, but instead on the probability that a certain set of them happened. Since we have no idea what the probabilities are since it's still an open question, drawing conclusions from this lack of knowledge is an argument from ignorance.

This is precisely what Plantinga's paper discusses. Why do I need to repeat what's there? You're wanting to discuss it with me, and have me present the argument, but you don't think it's worth wasting your time when Plantinga presents it? How is the time you spend with me any more valuable than that you spend with Plantinga?

Hopefully you'd be able to provide a more succinct answer than 60+ pages of text, but I might be mistaken.

This viewpoint of yours is by no means universally accepted. It has a number of interesting consequences, and deserves a thread on its own. For example:
* What then do you think of deductive reasoning in science from empirical evidence? Or do you think that is worthless as well? (Eg. PE=mgh for all falling objects on earth. This rock is falling. Therefore, its PE = mgh)

Wow, that's a terrible example. Your premise #1 is the result of inductive reasoning, not deductive.

* What do you think of deductive reason that led to hypotheses to be tested, and turned out confirmed precisely because of the deductive argument initially presented?

That they were simply interesting ideas until tested against the real world.

* What about the deductive reasoning we do every day of our life? (Today is Sunday. The library is closed Sundays. Therefore, the library is closed today). Do you give a special status to some forms of deductive reasoning, but reject others? What makes you think some have greater value than others? Surely if the premises are sound, and the argument valid, we should give it consideration no matter what the conclusion.

The majority of reasoning we do from day to day is inductive, unless you can provide a deductive proof that "given x happened every Sunday before now, therefore x will happen this Sunday."
But in any case, the fewer assumptions the better, and obviously when the conclusions are able to be tested against the real world it provides more certainty that personal bias has been eliminated.

Do you think empirical evidence is the only evidence worth considering? If so, how can you empirically prove that statement without question begging? Surely the a priori acceptance of deductive reasoning is needed to give empiricism a firm foundation

Can you provide an example of non-empricial evidence?
To answer your question, I think deductive reasoning is fine as long as the assumptions are valid. But for arguments like Plantinga's where neither his assumptions or conclusions can be tested, I'm pretty skeptical.

What is TAG

Teleological argument for god. Google provides tons of examples.

For example, imagine I make the statement, "it is highly probable that any person will accept the jackpot when they win in a lottery". Do I need to give an exact probability to make my statement? No. It is sufficient for me to present reasons explaining why the probability is high. You can't say my argument is false because I can't tell you if the probability is 0.95 or 0.97. After all, I've demonstrated that it is >> 0.5, and that's sufficient.

This can be easily measured based on past events, since there have been lots of lotteries, lots of winners, and lots of observations of their behavior. We have no similar evidence of multiple runs of consciousness evolving, so I don't see that this example is in any way relevant.

That is exactly the same with Plantinga's argument. For him to draw a conclusion, he needs to give reasons why a given probability is >>0.5, <<0.5, or ~= 0.5. That is more than sufficient to come up with a probability for the conclusion. Does he provide this in his paper? Yes he does. Exact numbers are not needed, nor even possible to provide. But values in a range large enough to draw an inference are possible, and in fact provided.

Again, there's no way he can do this given that he (along with everyone else) has no idea what mechanisms link belief and behavior. To calculate probability of an event, either you have an understood mechanism that provides predictive power, or you have a large enough sample set of previous events that lets you draw some inductive conclusion about the outcome of future events. The author has neither, so this is a third case, where he tries to reason in the absence of theory or evidence. I did the same and for some reason you rejected it out of hand, but you expect me to behave differently.

And as the paper I referenced below shows, Plantinga gives the probability of one of his alternative explanations as "inscrutable". While not technically a synonym for "unknown based on current knowledge", it's at least honest about his (and everyone else's) lack of understanding about the subject.

 

[Apollo Rhetor]

drawing conclusions from this lack of knowledge is an argument from ignorance.

It might be called foolish, but I don't think it's an "argument from ignorance". My understanding of an "argument from ignorance" is that you say something like "we don't know in which way beliefs are related to behaviour, therefore they can't be related". That doesn't seem to me to be the same as what Plantinga is saying.

And you said "Since we have no idea what the probabilities are since it's still an open question" - Plantinga, however, was trying to start the discussion, giving some probabilities. Again, I'm not seeing the link to an "argument from ignorance" - you haven't established which portion of his argument is from ignorance:
http://en.wikipedia.org/wiki/Argument_from_ignorance

I'd like to see you provide an argument for the way in which you think this is an argument from ignorance. What you seem to be saying is that Plantinga assumes he knows more than he does - which may be the result of ignorance, but it is not the same thing as an "argument from ignorance".

Hopefully you'd be able to provide a more succinct answer than 60+ pages of text, but I might be mistaken.

I think you were.

Wow, that's a terrible example. Your premise #1 is the result of inductive reasoning, not deductive.

You've misunderstood the point of my example. A deductive argument is one where if the argument is valid, then the conclusion will necessarily flow from the premises. A deductive argument is said to be sound if the premises are true.

A deductive argument's premises may be established by empirical evidence, or by inductive arguments...but the fact that a premise is inductively or empirically justified does not make the argument itself inductive. The example I gave was indeed deductive, and rested upon an inductively demonstrated premise. I want to know, if you think that deductive arguments are of little value, how you would use arguments like the above.

I was trying to show you how deductive reasoning is still necessary when we have empirically founded premises.

That they were simply interesting ideas until tested against the real world.

So, you don't think that the fact that a person was right for the very reasons they gave means anything?

The majority of reasoning we do from day to day is inductive, unless you can provide a deductive proof that "given x happened every Sunday before now, therefore x will happen this Sunday."

Again, my premises were inductively founded, but the argument itself was deductive.

Can you provide an example of non-empricial evidence?

I can't, because I shouldn't have used the word "evidence", sorry. The word evidence seems to imply inductive weight. Your answer to the question seems satisfactory though, that deductive arguments are fine if the premises are sound. But that's always been assumed. You had said earlier, "I find philosophy similar to early attempts at science, where people thought that they could derive information about the real world by making various assumptions and using deductive logic"...there seems to be a discrepancy here with what you're saying. Can deductive reasoning be used to make inferences about the real world, or not?

Teleological argument for god. Google provides tons of examples.

A search of TAG in google provides tons of examples of many different things

Again, there's no way he can do this given that he (along with everyone else) has no idea what mechanisms link belief and behavior. To calculate probability of an event, either you have an understood mechanism that provides predictive power, or you have a large enough sample set of previous events that lets you draw some inductive conclusion about the outcome of future events. The author has neither, so this is a third case, where he tries to reason in the absence of theory or evidence.

I don't believe this is true, and neither is it universally accepted. If we accept your argument, that we need to either understand the mechanism or have a large sample set, then we would not be able to reason that N&E is likely to produce rational beings. Yet this is exactly what a number of people who accept N&E have argued. Plantinga in an older paper quotes Quine:
"What does make clear sense is this other part of the problem of induction: why does our innate subjective spacing of qualities accord so well with the functionally relevant groupings in nature as to make our inductions tend to come out right? Why should our subjective spacing of qualities have a special purchase on nature and a lien on the future?
There is some encouragement in Darwin. if people's innate spacing of qualities is a gene-linked trait, then the spacing that has made for the most successful inductions will have tended to predominate through natural selection. Creatures inveterately wrong in their inductions have a pathetic but praiseworthy tendency to die before reproducing their kind"

Now, if the Darwinist is allowed to argue that the probability of R on N&E is high, then the theist should likewise be allowed to present arguments that the probability is low. But if you think that neither should be permitted to discuss the probabilities on this topic, then perhaps you'd more appreciate Plantinga's second argument, that the probability is inscrutable and therefore we should be agnostic about R on N&E? (mentioned below)

I did the same and for some reason you rejected it out of hand, but you expect me to behave differently.

Where? I'm not sure which bit you're referring to.

And as the paper I referenced below shows, Plantinga gives the probability of one of his alternative explanations as "inscrutable". While not technically a synonym for "unknown based on current knowledge", it's at least honest about his (and everyone else's) lack of understanding about the subject.

Plantinga actually presents two arguments against naturalism:
1. That the probability of R given N&E is low
2. That the probability of R given N&E is inscrutable

I've been referring exclusively to his first argument, and not the second. That paper you linked to discusses both, I think.

 

[Punchy]

Lewis, like Chomsky, is usually criticized on ideological grounds. When it comes to the substance of his arguments, rather than your preconceived notions, Lewis wins bar none.

 

[KCfromNC]

I'd like to see you provide an argument for the way in which you think this is an argument from ignorance. What you seem to be saying is that Plantinga assumes he knows more than he does - which may be the result of ignorance, but it is not the same thing as an "argument from ignorance".

The argument from ignorance ... is a logcial fallacy in which it is claimed ... that a premise is false only because it has not been proved true.

That sums up what I'm talking about. As in "scientists can't show conclusively that evolution can produce true beliefs, therefore I'll conclude that it's unlikely." It's not exactly assuming the premise to be false, but in a probabilistic argument assuming it unlikely is very much the same concept.

I was trying to show you how deductive reasoning is still necessary when we have empirically founded premises.

Maybe so, but this example isn't all that useful because we don't ever have premise #1 to work from when working in the real world. The problem of induction is a lot more complex than that. But it works in the real world, so we do what we can to understand it and move along to more interesting material.

So, you don't think that the fact that a person was right for the very reasons they gave means anything?

It means that their assumptions and deductive skills were correct, but that and $4 will get you a cup of coffee. Given the limitations of observation and induction, there's no way a priori to be sure that the assumptions or deduction means anything in relation to the real world.

You had said earlier, "I find philosophy similar to early attempts at science, where people thought that they could derive information about the real world by making various assumptions and using deductive logic"...there seems to be a discrepancy here with what you're saying. Can deductive reasoning be used to make inferences about the real world, or not?

As a pure process of thinking and deducing, it's not particularly reliable. People's biases make it way too easy to slip up and assume things that confirm preconceptions.

A search of TAG in google provides tons of examples of many different things

Yep, true. My bad. I though I had also mentioned presupposionalists, which would have narrowed it down a bit.

I don't believe this is true, and neither is it universally accepted. If we accept your argument, that we need to either understand the mechanism or have a large sample set, then we would not be able to reason that N&E is likely to produce rational beings. Yet this is exactly what a number of people who accept N&E have argued. Plantinga in an older paper quotes Quine:
"What does make clear sense is this other part of the problem of induction: why does our innate subjective spacing of qualities accord so well with the functionally relevant groupings in nature as to make our inductions tend to come out right? Why should our subjective spacing of qualities have a special purchase on nature and a lien on the future?
There is some encouragement in Darwin. if people's innate spacing of qualities is a gene-linked trait, then the spacing that has made for the most successful inductions will have tended to predominate through natural selection. Creatures inveterately wrong in their inductions have a pathetic but praiseworthy tendency to die before reproducing their kind"

Now, if the Darwinist is allowed to argue that the probability of R on N&E is high, then the theist should likewise be allowed to present arguments that the probability is low.

Notice the difference - Quine is saying that the tentative model is "some encouragement" without asserting that beliefs can be explained via naturalism. Plantinga is discounting this tentative model and claiming that the probability is either low or inscrutable and drawing a conclusion from that. At least in Quine's case, we know that natural selection occurs. I don't think I've seen any scientific research that demonstrates a mechanism which produces beliefs which are consistently wrong yet selectively advantageous. Given this, I know which premise I'll tentatively accept should I be forced to.

But if you think that neither should be permitted to discuss the probabilities on this topic, then perhaps you'd more appreciate Plantinga's second argument, that the probability is inscrutable and therefore we should be agnostic about R on N&E? (mentioned below)

I don't think it's inscrutable. I think it's unknown. Big difference.

Where? I'm not sure which bit you're referring to.

My first response was discussing how unlikely it was that evolution could consistently produce beings with false beliefs. It's based on near total ignorance of how beliefs could possibly evolve, but that's my whole point.

Plantinga actually presents two arguments against naturalism:
1. That the probability of R given N&E is low
2. That the probability of R given N&E is inscrutable

I've been referring exclusively to his first argument, and not the second. That paper you linked to discusses both, I think.

Which one is the true premise? When I see someone arguing from two mutually exclusive premises based on which argument he wants to make, I go back to my point that philosophical arguments are only as good as their assumptions. You understand my concern if each variation of his argument starts with different, mutually exclusive assumptions.