Empiricism and the Blind Man

[PLP]

It has been asserted that a blind person must take the existence of light and sight on “faith”; i.e. he must uncritically believe it to be true despite all the evidence of his senses. This is not a correct position.

It is true that a blind person cannot directly experience light. However, he can come to the scientific conclusion that many other people do in fact have some sort of sensory modality he does not have with as much scientific rigor as we ordinary sighted people come to any other scientific conclusion. And he can come to that conclusion using the sensory modalities that are available to him.

Suppose I were to claim that I myself possessed a “paranormal” sensory ability. I’m not saying that it’s supernatural or divine, merely that I can somehow sense things that ordinary people cannot. It is possible to scientifically test my claim by experiment.

I will leave the actual experiment for a while as an exercise to the readers.

 

[trth_skr]

PLP:

It has been asserted that a blind person must take the existence of light and sight on “faith”; i.e. he must uncritically believe it to be true despite all the evidence of his senses. This is not a correct position.

It is true that a blind person cannot directly experience light. However, he can come to the scientific conclusion that many other people do in fact have some sort of sensory modality he does not have with as much scientific rigor as we ordinary sighted people come to any other scientific conclusion. And he can come to that conclusion using the sensory modalities that are available to him.

Suppose I were to claim that I myself possessed a “paranormal” sensory ability. I’m not saying that it’s supernatural or divine, merely that I can somehow sense things that ordinary people cannot. It is possible to scientifically test my claim by experiment.

I will leave the actual experiment for a while as an exercise to the readers.

I would extend the EM spectrum into the infrarred (IR) (i.e., longer wavelength), then allow the blind person to “feel” the heat emitted. As I turned up the temperature, say on a metal filament, the blind person could then “feel” the intensity of heat increase at fixed distance.

Next the mathematics of EM distribution could be used to convince the blind person of the relation between temperature of the filament and emmitted black body radiation. Finally the blind person could understand that as temperature rose boyond some point, a portion of the spectrum would be emmitted in the wavelengthd detected by the eye (say 450 - 800 microns, roughly). The blind person would then have to accept that functioning eyes are capable of detecting these wavelengths, and a continuous mapping of of the wavelelngth could be made, that we interpret as color, etc.

Mark Wyatt
www.veritas-catholic.blogspot.com

 

[EnterTheBowser]

I wonder if it is physically or logically possible to construct a group of conscious beings and an environment such that there is some feature of this environment that is observable by us but which is in-principle unobservable by them. I’ve got no point to make; it’s a question I’ve been thinking about.

 

[john_doran]

trth_skr:

The blind person would then have to accept that functioning eyes are capable of detecting these wavelengths, and a continuous mapping of of the wavelelngth could be made, that we interpret as color, etc.

and what is the epistemological status of this “having to accept”?

 

[trth_skr]

john doran:

and what is the epistemological status of this “having to accept”?

We already have to accept to some degree that what we see, for instance, is in fact external to us; though some do not accept this.

Most empiricists would accept that there is no real distinction between “red” and yellow" beyond the wavelength of light involved. A metaphysicisit (a Christian and / or Platonist one, at least), may argue that since God created us with the ability to distinguish between the colors, there is a metaphysical reality underlying the differences, not readily apparent to us. An evolutionist may argue that ther is some “selective advantage” to being able to make this distinction… Anyway, this could go on, and I am not sure where ou are trying to go with it.

Mark Wyatt
www.veritas-catholic.blogspot.com

 

[PLP]

trth_skr:

I am not sure where ou are trying to go with it.

Well, it’s been asserted that the blind must take the existence of sight on “faith”, without empirical scientific support. I wish to contradict this argument.

 

[trth_skr]

PLP:

Well, it’s been asserted that the blind must take the existence of sight on “faith”, without empirical scientific support. I wish to contradict this argument.

Do you agree that this is a reasonable approach?

Mark Wyatt
www.veritas-catholic.blogspot.om

 

[PLP]

trth_skr:

Do you agree that this is a reasonable approach?

Sure.

But there’s an easier way, which can also detect even a sensory modality which cannot be continuously translated to an available modality.

 

[Neithan]

PLP:

Well, it’s been asserted that the blind must take the existence of sight on “faith”, without empirical scientific support. I wish to contradict this argument.

Actually, in my original post I stated (emphasis mine):

Neithan:

It would not be wise for a man born blind to base his reason purely on his four senses, since he cannot perceive everything that exists. He would need to rely on natural reason and faith that light exists–there are humans who live and move about him with much greater ease than he does, for example, and he could then quite naturally conclude that they possess an ability which he doesn’t. It is by natural reason that the man comes to accept the** existence of sight**. It is by faith that he comes to accept the existence of things which sight indirectly reveals to him–light–through the mediation of his human family and friends.

Subtle distinction. The underlying argument is that natural reason alone can point to the existence of God (or probability thereof), and I am using a parallel here with the blind man and the existence of sight. What sight reveals to him–light–must be accepted on faith, because he does not possess any ability to personally experience it–he does not personally possess knowledge which sight procures–which is necessary for purely reasoned knowledge. He does, however, indirectly experience sight through the mediation of his human family and friends, and can deduce that they possess such an ability with his reason.
trth_skr’s experiment to ‘feel’ light through heat is interesting, but only insofar as it further proves the existence of sight (which we already established is accessible to a blind person’s natural reason). Light and heat are still essentially different things, and the man must accept the existence of the former by faith.

To clear up any confusion–faith is simply the acceptance of knowledge based on authority rather than personal experience.

 

[trth_skr]

Neithan:

…Light and heat are still essentially different things, and the man must accept the existence of the former by faith…

Metaphysically, maybe. As I said, God chose to give us specific sensory perception in this small region of the electromagnetic spectrum. There may be a very specific reason why, and it may be beyond our knowledge (perhaps in the next life it will be known to us). Empericaly, light is only different through some form of definition. I.e., light and heat are electro-magnetic radiation at different wavelengths- part of a continuum wavelengths.

I think you are hinting at an underlying metaphysical reality.

Note that there are thermal imagers which can form images by detecting levels of heat. An interpertation needs to be applied to the measured heat (grey scale or false color, etc.), but uiltimately “heat vision” is the result. My hot cat, IFBU (now deceased):

(Please Note: This uploaded content is no longer available.)

Mark Wyatt
www.veritas-catholic.blogspot.com

 

[thistle]

Neithan:

Actually, in my original post I stated (emphasis mine):

Subtle distinction. The underlying argument is that natural reason alone can point to the existence of God (or probability thereof), and I am using a parallel here with the blind man and the existence of sight. What sight reveals to him–light–must be accepted on faith, because he does not possess any ability to personally experience it–he does not personally possess knowledge which sight procures–which is necessary for purely reasoned knowledge. He does, however, indirectly experience sight through the mediation of his human family and friends, and can deduce that they possess such an ability with his reason.
trth_skr’s experiment to ‘feel’ light through heat is interesting, but only insofar as it further proves the existence of sight (which we already established is accessible to a blind person’s natural reason). Light and heat are still essentially different things, and the man must accept the existence of the former by faith.

To clear up any confusion–faith is simply the acceptance of knowledge based on authority rather than personal experience.

FAITH:

www.newadvent.org/cathen/05752c.htm

 

[john_doran]

PLP:

Sure.

But there’s an easier way, which can also detect even a sensory modality which cannot be continuously translated to an available modality.

well, i suppose that if the blindness is simply a deficiency in the eye-brain delivery system (e.g. the optic nerve is damaged), then one could simply directly stimulate that portion of the peristriate region of the occipital lobe responsible for the perception of colour, and explain to the blind person that there are particles/waves in the world which are the cause of such phenomena in sighted people.

but, if by “a person born blind” we mean something like “an individual with a traumatized occipital lobe”, then direct stimulation would be impossible, in which case the individual would be incapable of the subjective experience of visual imagery. in that case it would be impossible in principle for that individual to come to believe in the existence of visual experience or the phenomena that causes it without “faith”.

 

[PLP]

There is a standard experimental protocol which can establish beyond a reasonable doubt the existence of any sensory modality unavailable to the experimenter, even if that modality is not continuously transformable to an available modality.

To even establish the claim of an unavailable sensory modality in coherent terms, there must be a person claiming the modality, and they must make a specific kind of claim: They can distinguish individual objects which the experimenter cannot distinguish.

For instance, if I claim color vision, I will claim that I can distinguish “green” objects from “red” objects; these objects appear to the experimenter as indistinguisably gray.

Out of sight (i.e. out of any known sensory modality) of the claimant, the experimenter randomly labels two apparently indistinguishable objects which the claimant has previously distinguished as “A” and “B”, and asks the claimant to distinguish them again. Repeated succeful trials of this experiment give a probability of 2^-n of successful distinction by chance, and provides a reason to believe that the claimaint does indeed have an additional sensory modality.

Obviously, the experimenter must take reasonable pains to ensure that available sensory modalities cannot be employed to distinguish the objects, but this is an implementation detail.

Of course, this type of experiment won’t work if the claimed additional sensory modality bears no relationship whatsoever to available sensory modalities, e.g. if the claimant appears to have access to a private “spirit world” separate from the physical world. However, if at least two people claim this sensory modality, we can experimentally test for independent agreement between occasion sentences by ensuring that the claimants cannot communicate by known sensory modalities; we could conclude that either they had access to the claimed modality, or at least they could communicate by an unknown modality.

We can use this method to prove color vision to a colorblind person, light to a blind person, sound to a deaf person, smell or sweetness to a person with a failure of smell or taste. We can use the second method to prove comprehension of a dead foreign language. None of these methods rely on the authority of anyone but the experimenter himself.

 

[john_doran]

ok - i see where you were going with that now. but that isn’t a demonstration to a blind person of the existence of “light”, or even of the physiology of sight - it is the demonstration simply of an ability to distinguish objects. as for what actually causes the ability to make such distinctions, the non-color-blind person could just as well explain the ability as god telling him which is which.

 

[PLP]

john doran:

ok - i see where you were going with that now. but that isn’t a demonstration to a blind person of the existence of “light”, or even of the physiology of sight - it is the demonstration simply of an ability to distinguish objects. as for what actually causes the ability to make such distinctions, the non-color-blind person could just as well explain the ability as god telling him which is which.

Well, he’s got to give the modality some name, and “sight” gets the job done. Additional experimentation can precisely determine the capabilities and limitations of sight; with sufficient experimentation, the blind person can know exactly as many empirical facts about light and its perception as the sighted. (Whether there are direct perceptual or experiential “facts” that can be known only to the sighted is a matter of no small philosophical controversy, but that’s a different story).

My point is that if there’s some sort of “extra” perception going on, it can be empirically demonstrated, with an appeal to no authority other than the experimenter’s own perceptions; no appeal to the authority of others is necessary. If religious believers claim that “faith” is some sort of sensory modality (rather than a set of subjective beliefs), there is a way to empirically test this claim.

 

[Neithan]

PLP:

My point is that if there’s some sort of “extra” perception going on, it can be empirically demonstrated, with an appeal to no authority other than the experimenter’s own perceptions; no appeal to the authority of others is necessary. If religious believers claim that “faith” is some sort of sensory modality (rather than a set of subjective beliefs), there is a way to empirically test this claim.

I think you are attacking a straw man here.
Faith is not the object of the analogy, but the means. I am comparing ‘sight’ with God and ‘light’ with certain religious dogmas e.g. the attributes of God, the existence of angels, etc. The former can be acquired by natural reasoning (not empirical, however) but the latter must be accepted on faith.

A person born blind–as stated in my original post–can (say, by scientific experiment) with his natural reason accept the existence of sight. He must accept any knowledge of reality which is accessible by sight alone–e.g. light–on faith, on the authority of those around him who fully possess sight.

Basically, a born blind man cannot accept the concept of ‘colour’ nor a born deaf man the concept of ‘music’ except by a twofold process:

1. 
   *]natural reason: accepting the existence of ‘sight’ and ‘hearing’
   *]faith: accepting the knowledge acquired only by sight and hearing on the authority of those who possess it.
   
   This is the same rational process used in theistic religion (such as Catholicism). This demonstrates that pure empiricism is not reliably capable of fully discovering reality.
   
   NOTE: faith is not a ‘sensory modality’ nor a ‘set of subjective beliefs,’ (that is more aptly termed ‘religion.’) Faith is accepting knowledge on authority. It’s a part of daily life. You exercise this every time you believe your doctor’s medical advice, a history book or documentary, etc. Faith is pretty much how we teach our children anything–may as well close down the schools if we are going to abandon it.

 

[PLP]

Neithan:

I think you are attacking a straw man here.
Faith is not the object of the analogy, but the means. I am comparing ‘sight’ with God and ‘light’ with certain religious dogmas e.g. the attributes of God, the existence of angels, etc. The former can be acquired by natural reasoning (not empirical, however) but the latter must be accepted on faith.

If you are going to draw the analogy between religious dogma is to God what light is to reality, then you must establish the essential property of the latter case, which is that sight gives us independently consistent occasion statements about reality.

Religious dogma does not, however, appear to give independently consistent occasion statements about God.

We must differentiate between whether dogma is to God what light is to reality or whether (with all due respect) dogma is to God what Jo Rowling is to Harry Potter.

He must accept any knowledge of reality which is accessible by sight alone–e.g. light–on faith, on the authority of those around him who fully possess sight.

I disagree. I don’t think there’s a single statement of fact about light (include the fact, “light exists”) which cannot be discovered by a blind person.

As to whether direct experience constitutes a kind of “knowledge” in this sense, that’s a completely different question. We all have to take each other on the other’s authority regarding subjective experience, but that’s an entirely different philosophical problem. The science of human cognition and consciousness is still very young, so we’re speculating in a scientific vacuum.

Basically, a born blind man cannot accept the concept of ‘colour’ nor a born deaf man the concept of ‘music’ except by a twofold process:

1. 
   *]natural reason: accepting the existence of ‘sight’ and ‘hearing’
   *]faith: accepting the knowledge acquired only by sight and hearing on the authority of those who possess it.

1. 
   This is the same rational process used in theistic religion (such as Catholicism). This demonstrates that pure empiricism is not reliably capable of fully discovering reality.
   
   But I don’t think that item (2) above is any different from anyone taking someone else’s subjective experiences on their authority. And there are no statements of fact regarding objective reality that ever have to be taken on another’s authority. It’s not an argument that empiricism cannot “fully” describe objective reality. And even (2) could well fall when we’re capable of doing better science.
   

   NOTE: faith is not a ‘sensory modality’ nor a ‘set of subjective beliefs,’ (that is more aptly termed ‘religion.’) Faith is accepting knowledge on authority. It’s a part of daily life. You exercise this every time you believe your doctor’s medical advice, a history book or documentary, etc. Faith is pretty much how we teach our children anything–may as well close down the schools if we are going to abandon it.

   The analogy is inapt. When I accept the authority of ordinary expertise, I’m just being lazy in a sense. There’s nothing that a doctor or historian knows that I cannot know in principle. And I’ve familiarized myself with their methodology and sources and I do in fact have some specialized knowledge that they have. The thelogian, or priest, OTOH, says things about God that I can’t figure out how I myself could know. He just arbitrariy declares things to be true, and expects me to believe them just because he says so.

 

[john_doran]

PLP:

My point is that if there’s some sort of “extra” perception going on, it can be empirically demonstrated, with an appeal to no authority other than the experimenter’s own perceptions; no appeal to the authority of others is necessary. If religious believers claim that “faith” is some sort of sensory modality (rather than a set of subjective beliefs), there is a way to empirically test this claim.

for what it’s worth, you seem to be making a category mistake here: to the extent that (some) religious believers claim insight derived from a kind of “sense” of the divine, it is a perception of a supernatural, non-empirical entity/existence, so there’s no reason to believe that it could be empirically verified.

of course, as i have always maintained, empirical verification isn’t a necessary condition for reasonable belief.

 

[john_doran]

PLP:

And there are no statements of fact regarding objective reality that ever have to be taken on another’s authority.

this is either (pragmatically) false or irrelevant.

for example, all historical facts are incapable of empirical verification, at least of the kind you seem to be talking about here (i.e. personal execution of repeatable experiments that match predictions). you could, of course, when confronted with the claim “there was a world war between 1939 and 1945” go to various sites of those purported battles to attempt to discover archaeological confirmation of the claims made about the war, but in the end, a few bullets or holes that may or may not be craters or big ships at the bottom of the sea, etc. etc., are equally consistent with other, more parsimonious theories (i know you love parsimony). which means that, in the end, the distinguishing epistemic factor will always be testimony.

realistically, i will never be able to go into space to look at the world and see that it is a giant sphere. i will never be able to go to the bottom of the ocean to verify that the pictures in the national geographic magazine that claim to be of the marianis trench actually are. i will never be able to set foot on the moon and finally prove - contra the conspiracy theorists - that we went there. and so on.

of course, perhaps you are simply stating the principle of verification, or something close to it: a proposition is meaningful only if it is in principle empirically verifiable or analytic. but, itself being neither in principle empirically verifiable nor analytically true, the principle must therefore be meaningless…

so. where we’re left is that reliance upon testimony in the formation of our beliefs is unavoidable, and i think it is entirely possible to have warranted beliefs the basis of which is testimonial evidence.

PLP:

The thelogian, or priest, OTOH, says things about God that I can’t figure out how I myself could know. He just arbitrariy declares things to be true, and expects me to believe them just because he says so.

this isn’t really true, either. given that we’re on a catholic board here, we must assume a catholic perspective on this kind of point (or at least i am, in fact, going to, whether or not i must). there have been a lot of theologians and priests throughout the ages that have said things about god that have been rejected by the church as being incompatible with basic theological principles, which principles have held firm for 2000 years. so there is a bulkwark of truth to which verifying appeals can be made.

for someone who doesn’t believe either in god or in the indefectibility teaching authority of the church as guaranteed by god, the principles themselves will seem arbitrary, and so be it. for us catholics, they’re not.

 

[PLP]

john doran:

for what it’s worth, you seem to be making a category mistake here: to the extent that (some) religious believers claim insight derived from a kind of “sense” of the divine, it is a perception of a supernatural, non-empirical entity/existence, so there’s no reason to believe that it could be empirically verified.

of course, as i have always maintained, empirical verification isn’t a necessary condition for reasonable belief.

It’s not necessarily a category “mistake”; I suspect, however, we have different ontological categories.

Empirical just means available to some sense. A “sense” of the divine is just that, an empirical observation. Of course, the ontological interpretation of that sense is what’s under discussion.

My experience with sensory reports attributed to the “supernatural” is that they are just as inconsistent as we would expect if they were artifacts of the imagination with features inculcated by cultural/social knowledge. This analysis doesn’t rule out the supernatural, but any supernatural analysis is going to have to include the same natural analysis to explain the inconsistencies and then add additional entities (the actual existence of the supernatural). Since I prefer simplicity, I stick with the natural interpretation.