Saturday, October 25, 2008

Reliable belief-producing faculties

Al: I think I've hit a better epistemic system: A belief is justified if and only if it is produced by a belief-producing cognitive faculty that is properly functioning.

The Barefoot Bum: Interesting, Al; a bold formulation! But I'm not sure that I understand you completely. How do we know that some belief-producing cognitive faculty is or is not properly functioning?

Al: First, let's talk about a faculty that we can't believe is properly functioning; that may shed some light on the subject.

TBB: Fair enough, go on.

Al: Consider a faculty that has been formed by a process of evolution. Clearly such a faculty cannot bet considered properly functioning in an epistemic sense.

TBB: Why not?

Al: Well, evolution selects for survivability and reproductive success, correct?

TBB: That's the theory, yes.

Al: So we must conclude that a faculty produced by evolution contributes to survivability and reproductive success. But that's a very different thing than justification of truth.

TBB: Is it?

Al: Sure. Suppose, for example, that a primitive human being had the belief that tigers were benign cooperative beings. Suppose further that whenever this human being saw a tiger, he believed that the tiger wanted to play a friendly game of hide-and-seek, and the human being tried to hide. This is a clearly false, unjustified belief, yet it would promote this human being's survivability, would it not?

TBB: I suppose it would, but...

Al: Wait! I have more.

TBB: Please go on.

Al: Suppose, however, that some faculty were created by an omnipotent, omniscient, omnibenevolent God. Surely we could hold a priori that such a faculty was reliable.

TBB: Perhaps so! But I still have some questions. First, in your evolution example, you talk about the content of a belief (tigers are benign beings who like to play hide-and-seek) independently of the physical expression of that belief (hiding from the tiger).

Al: Well, yes.

TBB: It's easy to take an omniscient philosophical perspective, but you're not asserting that you really are actually omniscient, I hope!

Al: No! Of course not!

TBB: First, you're just assuming you're correct, that tigers really are dangerous beings who want to eat us.

Al: Well, aren't they?

TBB: Well, I think so, but maybe I'm wrong. Maybe tigers really are benign beings who just like to play hide and seek, and you and I are just being paranoid.

Al: That seems far-fetched!

TBB: Perhaps. But let's look at the problem from a different perspective: how do we actually determine the content of a belief independently of its physical expression? On what basis could we, in principle, actually determine that our primitive human being actually has a false belief instead of the true belief that tigers are dangerous and will eat him if he doesn't hide?

Al: I suppose we would just ask him.

TBB: But isn't speech a physical act? We're no longer determining the content of a belief independently of the physical expression of that belief.

Al: Perhaps, but speech is a very different kind of physical act; surely evolution cannot select for the particular words we use to describe our beliefs.

TBB: Good point. But I still have a question: before we can ask him about his beliefs, we have to learn his language. And to learn his language, we can only correlate his words with his non-speech actions. So we're back to determining his beliefs dependent on the physical expression of those beliefs.

Al: But perhaps he uses the same words to talk about hiding from a tiger that he uses to talk about playing a friendly game of hide-and-seek with his truly benign neighbors.

TBB: Perhaps he might. But the question goes deeper: does he play hide-and-seek with a tiger in the same way that he plays hide-and-seek with his neighbors? I know when I played hide-and-seek as a child, I would laugh and be delighted when I was found. I definitely did not try to fight off and kill the child who found me.

Al: I hope not! You would have been quite the monstrous child, killing off your classmates like that.

TBB: I probably would not have survived very long. Likewise, if your primitive human laughed and was delighted when the tiger found him, if the didn't try to fight off and kill the tiger, he also would not survive very long.

Al: Hmmm... That's a good point.

TBB: Even if he were to use the same words for two different situations, if his behavior differs in those situations, we must conclude that he has different meanings for the same word. Perhaps he means "hide-and-seek" ironically or metaphorically when applied to the tiger.

Al: I suppose we can't rule that out; we have plenty of experience with irony and metaphor in our own language.

TBB: Furthermore: If his behavior is identical with our own behavior in all respects, we have no basis to conclude that the words he uses to label that behavior have a different underlying meaning than our own words. And if his behavior differs from our own, then presumably one is superior to the other in terms of survivability, and we can tell based on physical expression that one is correct and the other incorrect.

Al: But what if there's no difference in survivability?

TBB: Then by what virtue would you say your beliefs are true and his false? Is it true that one must hide behind a tree and false to climb a tree, even if both are equally effective at avoiding being eaten by a tiger?

Al: Well...

TBB: Let's turn to your God-given faculty.

Al: All right.

TBB: First of all, you've created four premises; you've made four assumptions.

Al: Four?

TBB: Yes, four: 1) God exists; 2) God is omnipotent; 3) God is omniscient; 4) God is omnibenevolent.

Al: OK, when you put it that way, I suppose we have four premises. But those are not very controversial premises.

TBB: Perhaps not. But I'm confused; perhaps my reasoning is poor... perhaps my cognitive faculties are not properly functioning. How do you get to the reliability of some faculty from these premises?

Al: The reasoning is simple: An omnibenevolent God would want us to have reliable faculties; an omnipotent God would have the ability to grant us those faculties; an omniscient God would know how to do so. Q.E.D.

TBB: I'm starting to see. But please forgive me: There's one step there I'm not quite sure about.

Al: It seems clear to me: what's your question?

TBB: I don't quite get the first part, "An omnibenevolent God would want us to have reliable faculties."

Al: Why wouldn't an omnibenevolent God want us to have reliable faculties?

TBB: Well... suppose — and if you can take an omniscient philosophical perspective, I hope you'll grant me the same privilege — suppose it were good that we had unreliable faculties? Such a premise doesn't entail a logical contradiction, does it?

Al: Well... I'm sure it does, but I can't figure out how right now.

TBB: Well, if you think of something, let me know. In the meantime, if it's good for us to have unreliable faculties, it would be no surprise that we would have the false belief that it's good to have reliable faculties.

Al: But then we wouldn't know anything! That's just epistemic nihilism.

TBB: Of course. But we can't exclude the possibility a priori. But I'll be charitable: we have four premises already; a fifth won't kill us: It's good to have reliable faculties.

Al: All right, so it all works out, right?

TBB: Not so fast!

Al: Hmmm?

TBB: Let's look at our reasoning:

P1: God exists
P2: God is omnipotent
P3: God is omniscient
P4: God is omnibenevolent
P5: reliable faculties are good
C: human beings have reliable faculties

Al: ok.

TBB: I have a question: Why should human beings have reliable faculties?

Al: What do you mean?

TBB: I mean, perhaps dolphins, or orangutans, or perhaps even rocks have reliable faculties; perhaps God doesn't really care what kind of faculties human beings happen to have.

Al: I suppose you're going to make me add another premise.

TBB: Mais oui. So now we have:

P1: God exists
P2: God is omnipotent
P3: God is omniscient
P4: God is omnibenevolent
P5: reliable faculties are good
P6: God wants human beings to have reliable faculties -or- God wants what's good for human beings
C: human beings have reliable faculties

Al: Are we done now? Or do you want a seventh premise?

TBB: I think six will do to make my point.

Al: Which is?

TBB: You've created seven premises and a careful chain of valid deduction.

Al: I'm glad you admit it!

TBB: Gladly. But out of all that, you've said nothing more than our faculties are reliable! No other conclusion follows from your premises.

Al: But at least I've explained why we have reliable faculties.

TBB: You haven't explained anything; all your premises say nothing more than the simple assumption that our faculties are reliable.

Al: As if by magic?

TBB: What, a supernatural deity isn't magic?

Al: Well...

TBB: There's another problem, though.

Al: What's that?

TBB: You're not saying that our faculties are perfect, right? Just reliable; good enough so that the beliefs formed are mostly true.

Al: Well, yes. Everyone makes mistakes.

TBB: Your "explanation" does not account for those mistakes, neither the pattern of mistakes, how we can detect them, nor why we should make mistakes at all.

Al: Well, I'm talking at a high level; I'm sure all these details can be fixed up.

TBB: Sure they can. But at the end of the day you're going to have to say:

P1: God exists
P2: God is omnipotent
P3: God is omniscient
P4: God is omnibenevolent
P5: God wants us to have faculties that err when (something)
P6: God wants us to have faculties that are correct when (something else)
P236: God wants us to have faculties we can tell are erroneous when (something)
P237: God wants us to have faculties we can tell are are correct when (something else)
Definition: Reliable faculties have the above characteristics
Pn-1: It's good (indeed optimal) to have reliable faculties
Pn: God wants human beings to have reliable faculties
C: Human beings have reliable faculties

Al: Well, all right.

TBB: So in practice, you just list all the characteristics of human faculties, call that "reliable", and assume that God exists, etc. wants us to have them.

Al: Well, when you put it that way...

TBB: Even if we could do no better than to just list all the characteristics of human faculties, we can chop off the first four premises, take out "God wants us to..." from the rest of the premises, and say exactly the same thing. No additional conclusions follow from these extraneous premises.

Al: But these premises might be true; there's no logical contradiction.

TBB: That's not a very high bar. If we don't care how many premises we have, then I could concoct some fantastic story about the Flying Spaghetti Monster, and the conflict between the pirates and the ninjas, and how the ninjas stole the spark of reliable cognitive faculties from the Holy Spaghetti Sauce and implanted them into human beings to aid them in their...

Al: Stop! I get your point. But that's clearly a ridiculous fantasy!

TBB: Of course it is. But it might be true; there's no logical contradiction.

Al: But...

TBB: And you're aiming at Christianity, right? Not just some abstract deistic God who creates cognitive faculties and then stands back and gets out of the way.

Al: Of course.

TBB: And in your story, you have talking snakes, talking donkeys, magical trumpets, angels, giants, people rising from the dead left and right, earthquakes, solar eclipses, four horsemen, the whore of Babylon, plagues, magic iron chariots... shall I go on?

Al: No, I get your point, but...

TBB: But nothing, Al! You object to a few pirates and ninjas? Seems like you're straining at a gnat and swallowing a camel. That's from your story, is it not?

Al: Yes, but...

TBB: I think your "reliable faculties" argument needs a little more work.

Al: Perhaps it does.


  1. The idea that only a deity can give reliable knowledge gathering features is quite reminiscent of Descartes. We can rely on our knowledge because God wouldn't like and our knowledge can only be reliable if God anyone?

    But, does our reliable but non infallible cognitive knowledge gathering bits tell us anything reliable about situations it didn't evolve in? ;)

  2. BB

    Est ce que tu parle Francais?

  3. I still like my succinct response to Plantinga's argument: Critters whose perceptual/cognitive faculties give them unreliable representations of (relevant aspects of) the world tend to end up as lunch for critters whose faculties give them more reliable representations.

  4. T4T: tristement, non; seulement l'expression désassorti.

  5. "...a belief-producing cognitive faculty that is properly functioning..."

    I knew at this point that I would not be convinced.

  6. Why break a butterfly upon a wheel? Because so many fucktards accept the EAAN I guess. Well done.

  7. Plantinga relishes in being stupid! Yes, other wise he would understand what science really has to say about his perverse, peculiar proposition! He wouldn't find God basic and so forth.
    I find he uses his immense intelligence to do double-talk , but Prof. Irwin Corey makes more sense!
    I let the superficial thinker find him and WLC intelligent agents when the two emit farragoes of sophistical, solecistic sophisms of wily ,woeful woo! They rank with Sylvia Brown[e].


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