Thursday, August 10, 2006

The brainy natural theologian in the vat

DM: We cannot escape this same problem within the field of theology or anywhere else -- what if we're just brains in a vat?

SH: Even a brain-in-a-vat can be a natural theologian. Theistic proofs like the ontological, cosmological, and teleological arguments, as well as new-fangled entries such as we find in Plantinga’s “Two Dozen or So Arguments” can all be retooled to address a brain-in-vat scenario.

As an a priori argument, the ontological argument, if sound, is just as applicable to a brain-in-vat scenario.

And one merely makes the suitable adjustments to the a posteriori arguments. The cosmological argument reapplied to an alien laboratory. The teleological argument replied to the design of the brain in the vat.

DM: This is a long-standing issue, as is the problem of other minds, and many other questions of philosophy. And your own position is not one in which these questions are given some solid solution -- proving other minds, or proving that our senses are reliable and that we aren't in the Matrix.

SH: You can also be a natural theologian in the Matrix.

DM: Instead, you retreat to the skeptical vantage when it comes to science, but the same "naivete" when it comes to theology -- that your experiences and sense knowledge of the Bible/revelation/etc are reliable knowledge, whereas scientific knowledge is not. You have a double standard.

SH: Several things wrong with this rejoinder.

1.Let’s play along with Danny’s Matrix scenario. Of course, Danny and I don’t believe that we are captives in the Matrix, but this is a useful limiting-case on what we can know.

Suppose the Bible I’m reading is really a virtual Bible. My eyes are not processing squiggles of ink on a sheet of paper. Rather, this is a computer simulation.

On the one hand, this means that, at one level, at least, we have a radical gap between appearance and reality.

I’m seem to see a Bible with my eyes, but I’m not using my eyes, and there’s no Bible to be seen.

But on the other hand, and at another level, the medium makes no difference to the Biblical propositions that I’m processing.

Even if the Biblical propositions were fed directly into my mind (or brain, if you prefer) by some neural interface, there is no discrepancy at that level, between the input and the output.

The Bible could be simulated, but the Biblical propositions could not be simulated.

2.Danny fails to distinguish between concrete and abstract objects, or concepts and percepts.

Is grass green? Maybe grass is really blue. I misperceive it as green. At that level, there’s a discrepancy between appearance and reality.

It’s a perceptual discrepancy with respect to a concrete object. What I see and what it is are two different things. It isn’t actually like the way I perceive it.

But what about the proposition that grass is green, or the proposition that grass is really blue?

Can I misperceive the proposition? No.

The proposition is an abstract object. An object of conception rather than perception.

3.Now, perception may be the means by which I acquire a knowledge of the proposition.

You can’t have a discrepancy between the proposition which the Matrix is feeding into my mind, and the proposition which I mentally register.

For if there were a discrepancy, I would be aware of the discrepancy. If the input were garbled in transmission, then the output would be gibberish.

Or even if it weren’t complete gibberish, there would be some obvious errors in transmission.

So, if it makes sense, then the process of transmission was successful.

4.Put another way, I could misperceive the medium of transmission. But what I cannot misperceive is the end-result.

A light wave or a sound wave can function as a carrier wave for abstract information. The information is encoded in the medium.

Suppose I misperceive the light wave. Perhaps the Bible looks like a red-letter edition when it’s really a gold-letter edition.

But that doesn’t affect the sense. Sense and sensation are two different things.

The sense may piggyback on sensation, but the sense is separable from the sensory medium.

If the sense is garbled in transmission, what you end up with is nonsense.

It’s not like misperceiving a color. And it’s not like a virtual illusion.

Even if the Bible were illusory, the Biblical propositions would not be illusory.

5.Not only so, but the propositions tell me something about the world. For example, they can confirm or disconfirm the fact that I’m a captive of the Matrix. They can describe what the world is really like, in one respect or another.

6.To drop your metaphor before it outlives its purpose, the Bible is not merely a sensory object. The Bible also has a lot to say about the sensible world.

And if the Bible is divine revelation (for which various arguments are available), then this supplies an external check on our subjectivity.

7.I do not regard the senses as unreliable. To the contrary, I regard our senses as reliable. But this raises a twofold question:

i) In what respect may we rely on our senses? What were they designed for?

I’d answer as follows:

a) They are a reliable means of our navigating and manipulating our physical environment.

b) They are also a reliable means of acquiring information about the sensible and spiritual world, but in a qualified sense.

I don’t think that our senses are equipped to tell us what the physical world is like, apart from the senses.

I don’t think our senses were ever designed to give us autonomous knowledge of the world.

In divine revelation you have word-media as well as sign-media. The sign-media were never meant to be independent of the word-media. Rather, the function of the sign is to illustrate the word, while the function of the word is to interpret the sign.

And I’d extend that revelatory model to sensation. The senses were never meant to operate without benefit of revelation. Rather, the senses are a conduit of revelation. And revelation, in turn, interprets the content of sensation.

DM: Not really, just taking an end-around approach. My position is and always has been that scientific knowledge is definitionally tentative and subject to falsification. Thus, what we "know" in science may be falsified tomorrow. The very nature of such "knowledge" evades absolutism. My point is that in using this knowledge and in continually testing and refining it, we have drawn the best conclusions that we possibly can, the most reliable conclusions that we can, and the best results for humanity...much better than merely armchair philosophy.

SH:

1.This is viciously circular. You can’t falsify something unless you already know something. Knowledge must furnish the point of reference for falsification.

2.As to “armchair philosophy,” this ignores the fact that the percipient has to begin with himself. With his mind.

You keep acting as if we can cut the observer out of the process and jump straight to the observational data.

The armchair is where we all begin. And, in a way, we never leave the armchair. For we never step outside of our own minds.

DM: And that is why, when you accused me of a parareligious view of science, I don't really mind the "stigma" -- I come back with a functionalist definition to religion: that whatever we see as the most important and useful thing we have can be considered our religion. The modern view of the functionalist definition is of course that a true religion must have some element of the supernatural involved. However, I'm allowing the functionalist definition to work here, and I'm using the pragmatic approach to return your scorn to your own lap -- that if I "worship" science, at least what I have devoted my life to studying and knowing has and will continue to do tangiable good for human beings. Is there a more noble quasi-religion to have?

SH:

1.Indeed, there is something more noble. And that is having a worldview which can ground the good as well as doing good for human beings beyond the reach of the grave.

You have no basis for moral absolutes. You have no basis for treating your fellow men as anything more than competitors.

And what one mortal can do for another mortal is pretty limited. Death row ethics.

2.What is more, you don’t have a monopoly on modern science. Christian theology is not opposed to medical science or modern technology.

We believe in doing good for our fellow man as well. We also have a firmer and broader basis for doing good than you ever will.

DM: This same question applies to your study of the Scripture, and your experiences of "revelation". All of those things go through the same senses and perceptive layers. What gives them more veracity? What makes your position coherent to reject sense knowledge that is filtered through methodological naturalism and continual refinement and selection...but accept sense knowledge gleaned from a bunch of dusty scrolls of unknown origins, and the way you feel (still sense perception) upon reading them and praying and such?

SH:

1.To some extent I just answered that question. Yes, all those things are filtered through the same sensory organs and perceptual layers. But if what comes out at the other end of the process is intelligible, then, at that level, there is, indeed, a direct correspondence between the input and the readout.

2.In addition, as James Anderson and I have pointed out, evolutionary epistemology is a recipe for scepticism. It has a way of cutting its own throat.

That’s entirely different from a framework in which the senses were designed by a superior mind to be truth-conducive.

3.To say the Bible is of unknown origin is a tendentious claim which disregards all the argumentation to the contrary.

DM: Your view is that man is corrupt (the observer) and thus his sense perceptions unreliable; but, for whatever reason, you hold the double standard explicated above. You say we could be brains in a vat on the one hand, but objects in God's universe on the other.

1.I already addressed that objection a month ago.

http://triablogue.blogspot.com/2006/07/pseudo-calvinistic-syllogism.html

2.Beyond that, the doctrine of total depravity has nothing to do with sensory perception. You’re grasping at straws.

DM: Scientific progress and knowledge is predicated upon sense reliability. You know this. It is a presupposition. It doesn't mean that we access the "raw" form of reality, but that there is a correlative relationship between "raw" and "perceived". Thus the "veil of perception" is taken to be non-distorted. Consider it one medium upon which is written a language of our brains (perception), which, when decoded, reveals "raw" reality. Do I really have to explain this to you? You know this is the position of those who hold to any form of scientific realism -- that our perceptions are reliable correlations to reality, even if encoded in a different medium.

A couple of basic problems:

1.What kind of correlation are we talking about? A causal correlation? Cause and effect?

Even though it can’t be proven, I’ll grant you that.

But this falls well short of an alethic correlation.

How do I withdraw money from an ATM? Do I have direct access to the greenbacks? No.

Rather, I push buttons which send a series of encoded signals to a computer program, and out pops the money.

There you have a causal correlation.

But I never see the money in the machine. All I see is the keyboard. And the keyboard bears no resemblance to the greenbacks.

So a causal correlation does not entail an alethic correlation.

It may afford you a practical knowledge of how to manipulate your environment, but it doesn’t afford you a knowledge of what your environment is really like. The pragmatic power of science is not an argument for the truth-value of scientific theorizing. You continually stumble over this elementary distinction.

2.A reliable ciphertext doesn’t tell you what the plaintext is like. It isn’t descriptive of the real world. So it doesn’t give you a true depiction of the world.

That is why your very own brand of scientific realism collapses into antirealism. The more you explain your position, the more it sounds like instrumentalism rather than realism.

DM: Exbeliever went over that a bit here as he talked about how both quantum theory and general relativity are true within their spheres of description, but not universally or absolutely true, but give us knowledge nonetheless:

SH: No, in context, we were talking about scientific progress. I had in mind the way in which a later theory like, say, Relativity, displaces an earlier theory like Newtonian physics. Both were successful. Yet they can’t both be right, now can they? So success and veracity are separable. And that remains a problem for scientific realism.

DM [quoting Exbeliever]: If it were the case, then, that human minds did not accurately reflect the structure of the world, it is still possible that human minds would be able to gain "knowledge" (i.e. the power of prediction) about the world even though they were unaware of how the world really operated. Just like a scientific theory does not have to be "true" to give us knowledge about the world, the human mind does not have to reflect the structure of the world in order for humans to gain knowledge about it.

In other words, it could be the case that human minds understand the world through Perception X. The world actually operates, however, through Perception Y. Even though Perception Y is the case, Perception X is such that it provides humans with a consistent ability to make predictions (i.e. gain knowledge) about the world. We know things through Perception X that are true not because Perception X is the case, but because Perception Y can also be understood in terms of Perception X.

Similarly, I see no reason to believe that a coherent, rational structure of the world and a mind that reflects this is necessary for communication.

SH:

1.Up to a point I agree with this. However, it plays straight into the hands of the teleological argument in order to coordinate appearance and reality.

And the need of such coordination is considerable heightened given the gap between appearance and reality, ciphertext and plaintext.

How is it possible for the perceptual-X to be a successful token of the Y-reality unless the code was already in place?

Unless the mind and the world were designed in a state of mutual preadaptation, you will not be able to bootstrap this coordination after the fact.

2.Likewise, this model is concordant with antirealism rather than realism. Since on this model, you can’t map X onto Y, you cannot say that evolution is true, or that modern cosmology is true, or that functionalism is true.

DM: It is thus something, versus the nothing offered by theology, as a tool whereby we can relieve pain and help human beings.

SH: You continually set up a false antithesis, as if science were a substitute for theology, and vice versa.

It may be a substitute for you because that’s all you’re left with. But a Christian doesn’t have to choose between technology and theology.

DM: Their veracity, or truth-value, increases as they evolve. They are not necessarily going to approach universal Truth, but they will describe the phenomena of reality more accurately and precisely with time, thus they are more true than previous theories...and it continues on from there.

SH: That’s very Popperian. And it disregards the criticisms of verisimilitude.

How do you know that something is truer unless you already have the truth to compare it to? You continue to pull rabbits out of the hat.

DM: This seems odd as a solution to the problem of perception. You posit another fundamental substance of which we are composed...fine, whatever, but how is it that this substance has perceptive powers which are not as internally circular and as externally unverifiable as "just" matter?

SH: It is not a solution to the problem of perception. Rather, it’s relevant to the fact that human knowledge is not limited to perception.

Therefore, we do have something besides sense knowledge to supply a source and standard of knowledge.

7 comments:

  1. I see many atheists bring up the brain in the vat problem tons of times. As if that problem will really do anything against theists. However, I think the credulity principle by Swinburne might be helpful here.

    ReplyDelete
  2. True, there's a difference between rational doubt and irrational doubt. Between doubting things we have reason to doubt (some positive contrary evidence) and pretending to doubt something just because we can dream up a dubious hypothetical.

    ReplyDelete
  3. This comment has been removed by a blog administrator.

    ReplyDelete
  4. There's nothing wrong with being filled with irrational doubts. In fact, I think irrational doubts are a great aid to my skepticism. If I didn't have them, I'd curl up like a dried Autumn leaf and blow away. So, please be sensitive and show a little compassion, OK? Don't try to explain away my irrational doubts, because then I really wouldn't exist anymore.....

    ReplyDelete
  5. I must plug my advisor. Check out Tony Brueckner's fine article on 'brains in a vat' in the Stanford Encyclopedia of Philosophy:

    http://plato.stanford.edu/entries/brain-vat/

    ReplyDelete
  6. I see many atheists bring up the brain in the vat problem tons of times. But then I ask them:

    Who would waste a perfectly good vat on a brain like mine?

    That usually stops dem cold.

    I think I'll go write a post about how brilliant I am on my blog!

    ReplyDelete
  7. But on the other hand, and at another level, the medium makes no difference to the Biblical propositions that I’m processing.
    Even if the Biblical propositions were fed directly into my mind (or brain, if you prefer) by some neural interface, there is no discrepancy at that level, between the input and the output.
    The Bible could be simulated, but the Biblical propositions could not be simulated.


    How would you be aware of language itself, and thus of reason, without the senses? You wouldn't.

    It’s a perceptual discrepancy with respect to a concrete object. What I see and what it is are two different things. It isn’t actually like the way I perceive it.

    But what about the proposition that grass is green, or the proposition that grass is really blue?


    Again, how would you know the concepts "grass" "blue" and "green" without sense experience?

    You can’t have a discrepancy between the proposition which the Matrix is feeding into my mind, and the proposition which I mentally register.

    What is the mind, or mental registration, without the senses? I'm not talking here about illusory sense experience, I'm talking about absolute skepticism towards your perceptions. If you had no sense input, let's imagine you were born in a sensory deprivation chamber, floating in some viscous liquid, and you had no input from the senses of any sort...

    The point I'm making is that you trust your senses to develop your mental processes, like language, which reasoning is completely dependent upon. And all of the concepts you use in making propositions are pretty meaningless if your perception of those concepts is distorted.

    I agree that some of your responses are sufficient to my objection, but I don't see how you can get past trusting in your own perceptions, and applying a sort of double standard to scientific observation.

    I haven't presented the brain in a vat as some primary argument, but as a reminder that if you doubt your perceptions, you start down a slippery slope towards such uber-skeptical positions.

    True, there's a difference between rational doubt and irrational doubt. Between doubting things we have reason to doubt (some positive contrary evidence) and pretending to doubt something just because we can dream up a dubious hypothetical.

    Such as doubting the reliability of perception?

    I'll reply more at length to the question of correlation after I do some reading on the topic.

    ReplyDelete