Are certain things unknowable?

Ed - Bill's confused with presuming that if the universe is all knowable, one has to be omniscient.

Post 41

Tuesday, December 20, 2005 - 3:16pm

Bill,

By the nature of the universe, there is never a time at which all human beings could possibly know everything that exists, because in order to know it, they would have to BE everywhere at the same time.

Yes Bill, I do get it, you know. But you still take me to be championing omniscience (which I'm not), and this provides you with a Straw Man that is awful easy to knock down. I philosophically escaped the omniscience charge when I improved (refined -- in response to your thoughtful criticism) my stance and highlighted that it was a potentiality thing (and specifically not an actuality thing). We don't have to actually be everywhere at the same time, in order for my improved position to hold true.

Ed

Post 42

Tuesday, December 20, 2005 - 4:19pm

Bill:

This is armchair speculation on ontology! How do you know that we could in principle become aware of any and every existent?

By definition. That something is an existent means that we can in principle become aware of it, otherwise the concept "existent" would be meaningless. To include things that are in principle unknowable would mean that the supernatural is an existent.

Post 43

Wednesday, December 21, 2005 - 2:11pm

Robert wrote,

Ed - Bill's confused with presuming that if the universe is all knowable, one has to be omniscient.

No, I wasn't saying that. I was saying that if the universe were all knowable, then we would have the potential to be omniscient, and it is that potential that I was saying we do not possess. We do not possess it, because at any particular time, there will always be something that is beyond our ability to identify. Now you can say that we have the potential to identify it in the future, but even if we did, there would always be something else that we could not then identify. No matter how much knowledge we acquire, there will always be more to know. In other words, no matter how long we live and how advanced we become, there will always be something that we cannot know. We will never reach a time when we know everything that exists.

I take it that Ed would agree with this, but argue that the potential still exists to identify in the future what we cannot presently identify. Even here, I don't think that one can make that kind of definitive statement. It doesn't follow, simply from the nature of an existent, that it is accessible to human knowledge. It may not be accessible to us, owing to the physical limitations on our means and methods of identification. Does man have the potential to run a mile in under three and half minutes? Maybe not, owing to his inherent physical limitations. Since our means of knowledge are also physical, there may be inherent limitations on the acquisition of certain kinds of knowledge.

Calopteryx writes,

By definition. That something is an existent means that we can in principle become aware of it, otherwise the concept "existent" would be meaningless. To include things [in existence] that are in principle unknowable would mean that the supernatural is an existent.

I don't follow this. What's meaningless about an existent which, due to the limitations on our physical means of knowledge, we are incapable of identifying? Calopteryx argues, in effect, that if something that exists is unknowable, then that which is unknowable (e.g., the supernatural) must therefore exist, which is the fallacy of affirming the consequent. It is true, of course, that if something doesn't exist, then it isn't knowable, but that doesn't mean that if something isn't knowable, then it doesn't exist. All it means is that if something is knowable, then it does exist. Hence, it does not follow that if something that exists is unknowable, whatever is unknowable must therefore exist.

- Bill

Post 44

Wednesday, December 21, 2005 - 3:13pm

Bill:

I don't follow this. What's meaningless about an existent which, due to the limitations on our physical means of knowledge, we are incapable of identifying? Calopteryx argues, in effect, that if something that exists is unknowable, then that which is unknowable (e.g., the supernatural) must therefore exist, which is the fallacy of affirming the consequent. It is true, of course, that if something doesn't exist, then it isn't knowable, but that doesn't mean that if something isn't knowable, then it doesn't exist. All it means is that if something is knowable, then it does exist. Hence, it does not follow that if something that exists is unknowable, whatever is unknowable must therefore exist.

I think we're talking about two different kinds of "unknowable". I'm not talking about those particular instances of things we can't know while we happen not to be there to observe them, and I don't think that is what this discussion is about. In that sense it's of course trivial that there are many things that are unknowable to us. IMO the question is whether there are things that are in principle unknowable, i.e. not some particular instances in a far-away galaxy or in the past, but general categories that we never could know even if they were "now before us". Such things would then be completely unaccessible, but that means that we'll never know that they exist, because the term "existence" (in the physical sense, and I suppose that's what we're talking about here) implies the possibility in principle of observing it, directly or via inference. If that possibility doesn't exist, the thing is by definition "outside nature", or in other words supernatural.

Post 45

Wednesday, December 21, 2005 - 4:13pm

Bill,

Does man have the potential to run a mile in under three and half minutes?

Yes. Man could, for instance, fly to the moon and run it that fast (bounding just as fast as a gazelle -- with a mere sixth of his usual body weight). Or man could stay here on Earth, develop shoes with springs, and essentially do the same thing. In fact, I could think of literally dozens of ways that man could run a mile in under 3.5 minutes. Why is that true? Because of unwavering potentiality.

I have viewed an electron micrograph of a dust mite (invisible to naked eye), I have viewed the surface of Mars -- but, but, but, what about limitations? Limitations, schlimitations -- there is no limitation in sight (and never was). Human ingenuity is not something that is "limited." The reason that this is true is that it is part (or all?) potentiality. Human ingenuity is not fully an actuality, and in this respect, it resembles the concept of infinity.

Our scope of awareness will increasingly widen, as it always has -- throughout all of written history. That's my main point. Given enough time and progress, any real thing could become knowable.

Ed

Post 46

Wednesday, December 21, 2005 - 4:49pm

And - because the universe is dynamic in its nature, and the span of duration so immense [for practical reasons infinite], there will always be more to gain knowledge on. Further, there is a law of diminishing returns on the amount of knowledge, while gained, which is retained - thereby adding, in effect, to the immeasurableness of knowledge to acquire - and in which removes the omniscience factor.

Post 47

Wednesday, December 21, 2005 - 6:22pm

I think we're talking about two different kinds of "unknowable". I'm not talking about those particular instances of things we can't know while we happen not to be there to observe them, and I don't think that is what this discussion is about. In that sense it's of course trivial that there are many things that are unknowable to us. IMO the question is whether there are things that are in principle unknowable, i.e. not some particular instances in a far-away galaxy or in the past, but general categories that we never could know even if they were "now before us". Such things would then be completely unaccessible, but that means that we'll never know that they exist, because the term "existence" (in the physical sense, and I suppose that's what we're talking about here) implies the possibility in principle of observing it, directly or via inference. If that possibility doesn't exist, the thing is by definition "outside nature", or in other words supernatural.

I think you've qualified the condition of knowability so much that the existent in question has become knowable "by definition." When you say that we could know it if it were "now before us," what you appear to be saying, in so many words, is that we could know, if we were in a position to know it. What, after all, does "now before us" really mean if not "directly accessible to our knowledge"? Suppose that something were "now before us" spacially, but too small to detect even with the most powerful microscope or sophisticated instrument. In that case, we could not know it, even if it were "now before us" (spacially), because of the physical limitation in our means of detection. The only way to circumvent this limitation is to construe "now before us" in a way that is non-spatial, but then it becomes nothing more than a synonym for "accessible to our knowledge."

Now you might reply that we could still detect it, if our instruments were sufficiently sensitive, but again, all you would be saying is that we could detect it if we were able to detect it, which is certainly true, but trivial and tautological. Does it follow that we must be able to detect it, merely because it exists? It is that conclusion that I am questioning. Maybe it's not possible, even "in principle" for us to make an instrument sensitive enough to detect it. "In principle" is like the phrase "now before us." We could know it "in principle" simply means we could know it "if we were in a position to know it." The real question is, can we ever be in a position to know it?

- Bill

(Edited by William Dwyer
on 12/21, 6:27pm)

Post 48

Wednesday, December 21, 2005 - 6:46pm

I wrote, "Does man have the potential to run a mile in under three and half minutes?" Ed replied, Yes.

Man could, for instance, fly to the moon and run it that fast (bounding just as fast as a gazelle -- with a mere sixth of his usual body weight). Or man could stay here on Earth, develop shoes with springs, and essentially do the same thing. In fact, I could think of literally dozens of ways that man could run a mile in under 3.5 minutes. Why is that true? Because of unwavering potentiality.

Ah yes. But you are altering the conditions, are you not? Did you really think I was referring to running it on the moon or with powerful springs attached to one's shoes? The next thing you'll be telling me is that man can run faster than the speed of light by running forward in a spaceship traveling at the speed of light. :-/ It always helps to have an unwavering respect for reality and its limitations. Primacy of existence, you know!

I have viewed an electron micrograph of a dust mite (invisible to naked eye), I have viewed the surface of Mars -- but, but, but, what about limitations? Limitations, schlimitations -- there is no limitation in sight (and never was). Human ingenuity is not something that is "limited." [Oh, yes it is!] The reason that this is true is that it is part (or all?) potentiality. Human ingenuity is not fully an actuality, and in this respect, it resembles the concept of infinity.

Nope. Potentiality has its limitations too. And, by the way, nothing is infinite, (saith "the Philosopher")!

Our scope of awareness will increasingly widen, as it always has -- throughout all of written history. That's my main point. [No argument there.] Given enough time and progress, any real thing could become knowable.

Not necessarily.

- Bill
(Edited by William Dwyer
on 12/21, 6:48pm)

(Edited by William Dwyer
on 12/21, 6:49pm)

Post 49

Thursday, December 22, 2005 - 6:56am

Bill:

I think you've qualified the condition of knowability so much that the existent in question has become knowable "by definition." When you say that we could know it if it were "now before us," what you appear to be saying, in so many words, is that we could know, if we were in a position to know it. What, after all, does "now before us" really mean if not "directly accessible to our knowledge"?

What I meant to say is that I'm not talking about something being unknowable while it is too far away or about something in the past. It's obvious that in that sense there are many things we'll never be able to know, but I think that wasn't what the original text by Branden was about. I think it's very unlikely that he had such a trivial interpretation in mind, which could of course easily have been refuted (of which he no doubt would have been aware).

Below I'll give an example of something "now before us" that is in principle unknowable.

Suppose that something were "now before us" spacially, but too small to detect even with the most powerful microscope or sophisticated instrument. In that case, we could not know it, even if it were "now before us" (spacially), because of the physical limitation in our means of detection. The only way to circumvent this limitation is to construe "now before us" in a way that is non-spatial, but then it becomes nothing more than a synonym for "accessible to our knowledge."

Now you might reply that we could still detect it, if our instruments were sufficiently sensitive, but again, all you would be saying is that we could detect it if we were able to detect it, which is certainly true, but trivial and tautological. Does it follow that we must be able to detect it, merely because it exists? It is that conclusion that I am questioning. Maybe it's not possible, even "in principle" for us to make an instrument sensitive enough to detect it. "In principle" is like the phrase "now before us." We could know it "in principle" simply means we could know it "if we were in a position to know it." The real question is, can we ever be in a position to know it?

Consider for example an electron moving around an atom. In the pre-quantum era the movement of the electron was thought to be a "classical" orbit, i.e. a definite curve in space around the nucleus of the atom. Since Heisenberg we know that it is in principle impossible to determine such an orbit; this is not some deficiency of the instruments we use today which might be overcome in the future, but an essential limitation inherent in nature. So the classical orbit (I'll use this term to distinguish it from the modern use of "orbit" as a synonym of "orbital" or "probability distribution") of the electron in an atom is something that is in principle unknowable. That makes it a meaningless concept, and therefore we say that such a classical orbit doesn't exist. This is something fundamentally different from the fact that something that is "now" (a tricky concept in this case, but never mind) existing in some remote galaxy is unknowable to us while we'll never get there in time. Even if we humans won't be able to observe it, there is the possibility that some alien existing there will observe it. Maybe there is no one there, but there is no essential physical argument that makes such an observation there impossible.

Post 50

Thursday, December 22, 2005 - 1:08pm

Here is Branden's original answer:

The concept of the 'unknowable' does not mean: that which is unknown at present. It means: that which, by its nature, cannot be known. To claim that a thing is unknowable entails a logical contradiction.
Of course, if by "unknowable," one means "that which by its nature cannot be known" (no matter what means of knowledge the knower could conceivably possess), then no, I don't think it's possible that something could be unknowable in that sense. What I was arguing is that it is possible for a thing to be unknowable, not in the sense in which it cannot by its nature be known, but in the sense in which it cannot by the nature of our means of knowledge be known, which is an altogether different claim.
To claim that a thing is unknowable, one must first know that it exists--but then one already has knowledge of it, to that extent. Further, to pronounce a thing unknowable, one would have to know enough about it to justify one pronouncement--but then the pronouncement and the justification would be in contradiction. If one makes such a pronouncement, or any pronouncement, without knowledge to justify it, then this is plain irrationalism.
True, to claim that a thing is unknowable in Branden's sense, one would have to possess this kind of knowledge, which is impossible for the reasons he states.
The assertion that a thing is unknowable carries the necessary epistemological implication that the speaker is omniscient--that he has total knowledge of everything in the universe and, from his unique vantage point, is able to proclaim that certain things are inherently beyond the reach of man's knowledge and understanding.

So, it depends on how one defines "unknowable." I was defining it not as something which by its nature cannot be known (by any consciousness whatsoever) but as something which, although it might be knowable to some non-human consciousness under some conditions, is not knowable to human consciousness under any conditions. Nor was I claiming that it was (necessarily) unknowable in this latter sense, but only that it might be unknowable--that one couldn't rule out that possibility simply on the grounds of its existence.

- Bill

Post 51

Thursday, December 22, 2005 - 3:29pm

Bill!

Ah yes. But you are altering the conditions, are you not?

Of course I'm altering the conditions. Why? Because I can. Man can. That is my motto, baby. Man can. If the naked eyes has limitations, then human ingenuity steps in to transcend those limitations -- time, after time, after time. In fact, altering conditions is what makes men man.

The next thing you'll be telling me is that man can run faster than the speed of light by running forward in a spaceship traveling at the speed of light. :-/

Hahaha! That's a good one, Bill! [sincerely]

Potentiality has its limitations too. And, by the way, nothing is infinite ...

Gotcha! It is actuality that has limitations, not pure potentiality. And there is nothing actual that is infinite -- but the temporal persistence of matter is something that is on an infinite (neverending) course.

Ed

Post 52

Thursday, December 22, 2005 - 5:56pm

Ed,

It is true that man's ingenuity can, to a great extent, enable him to transcend the limitations of his physical senses, but you can't say categorically that this can have no limitations whatsoever. As you point out, man can travel only so fast unaided, but his intelligence and ingenuity have allowed him to transcend these limitations by producing ever faster vehicles of locomotion. Does that mean that there is no natural limit on the speed of vehicular travel? Before he discovered that nothing could exceed the speed of light, he might have thought so, but he would have been wrong. He could not legitimately have inferred that since he was finding ever faster ways to travel, there was no conceivable limit on the speed that he could eventually attain.

By the same token, just as man is able to transcend the limitations of unaided locomotion by developing ever faster means of travel, so he is able to transcend the limitations of his unaided physical senses by developing ever more powerful telescopes and microscopes and ever more sophisticated instruments of scientific investigation and detection. Still, just as there is a natural limit on the rate of aided locomotion, which is the speed of light, so there may well be a natural limit on the extent of man's ability to penetrate the secrets of nature. At the very least, such a limit cannot be ruled out of court a priori, as you seem to be doing.

- Bill

Post 53

Thursday, December 22, 2005 - 6:23pm

Bill,

... just as there is a natural limit on the rate of aided locomotion, which is the speed of light, so there may well be a natural limit on the extent of man's ability to penetrate the secrets of nature. At the very least, such a limit cannot be ruled out of court a priori, as you seem to be doing.

Okay, here's the deal. Mentally divide reality into 2 parts -- that which is mental, and that which is extra-mental. It is clear that that which is extra-mental will always be actual. And we both agree that that which is actual -- is always something which has a natural limit (it will always have a "pre-ordained" identity). Now, you are taking this unbreakable rule (about extra-mental reality) -- and applying it to the mental. I believe that this is a category mistake on your part.

I agree that single entities (single individuals), being part of the natural world -- will have natural limitations. As I said before though, the TAKU (knowable universe axiom) applies to the species -- across all space and time. Your postulation (utilizing the weak analogy of extra-mental ~ mental) is that human ingenuity has a natural limit. I find this absurd. There is no evidence of a natural limit applied to ingenuity but, instead, evidence of geometric growth -- throughout all of written history.

In order to adopt your position, I find myself having to take that unbreakable, limitation-rule of all actuality (the ULRAA), and apply it to a potentiality (my TAKU is based on potentiality, not actuality). Now, it may seem that I'm speaking in Bantu here (e.g. ULRAAs & TAKUs), but I am trying to make this as plain as day: ingenuity, by definition, is not something that can be bottled. It is a capacity (like the capacity of gravity to maintain its pull on something) that does not have to have a limitation.

Ed

Post 54

Friday, December 23, 2005 - 11:22am

Ed,

Okay. Let's take your potentially limitless ingenuity and apply it to my example of locomotion. Are you saying that since man's ingenuity is potentially limitless there is no limit on how fast he can potentially travel? Or do you agree that no amount of human ingenuity can enable man to travel faster than the speed of light, because of the "extra-mental" limitations of reality? And if there is a natural limitation on how fast man can travel, human ingenuity notwithstanding, then why couldn't there also be a natural limitation on how much man can know, human ingenuity notwithstanding?

- Bill

Post 55

Sunday, December 25, 2005 - 8:39am

Bill, sorry for the belated response (my home computer is caput).

Are you saying that since man's ingenuity is potentially limitless there is no limit on how fast he can potentially travel? Or do you agree that no amount of human ingenuity can enable man to travel faster than the speed of light, because of the "extra-mental" limitations of reality?

Bill, I asked my 11 year old nephew about this and he told me that "the only way to travel faster than light is if you go through a black hole. His answer appears quite ingenius -- as black holes are capable of overcoming the speed of light (light's not fast enough to escape them).

If my nephew's right, then does your argument (which hinges on us never finding a way to travel faster than the speed of light -- just as my nephew has just postulated so) still stand?

Ed

Post 56

Monday, December 26, 2005 - 11:20am

It's the difference of crossing across the plains or going thru a tunnel, to keep the analogy of using the black hole... as such, it really doesnt violate the premises of speed limit.

Post 57

Monday, December 26, 2005 - 6:02pm

I asked Ed, "Are you saying that since man's ingenuity is potentially limitless there is no limit on how fast he can potentially travel? Or do you agree that no amount of human ingenuity can enable man to travel faster than the speed of light, because of the "extra-mental" limitations of reality?" He replied,

Bill, I asked my 11 year old nephew about this and he told me that "the only way to travel faster than light is if you go through a black hole. His answer appears quite ingenius -- as black holes are capable of overcoming the speed of light (light's not fast enough to escape them).

If my nephew's right, then does your argument (which hinges on us never finding a way to travel faster than the speed of light -- just as my nephew has just postulated so) still stand?

Ed, as you know, my IQ is only 115, and you expect me to answer that question?? Sorry, Ed, but you're testing the "limits" of my knowledge. Besides, don't you think it's a bit unfair to pit my meager understanding of physics against that of an 11-year old?! You could at least have chosen someone a bit older! Then I wouldn't look like such a fool, if I couldn't answer him! (The next time you see him, tell him there's a black hole inside my head that's preventing any knowledge from escaping!)

Seriously, it's my understanding that you see a black hole, not because it exceeds the speed of light, but because its mass is so concentrated that its gravitational pull prevents any light from escaping. Think of it this way: In order to escape the earth's gravitational pull, you need a certain velocity. That velocity is called the "escape velocity," which depends on the earth's mass. The greater the mass of the body from which you're trying to escape, the greater the escape velocity. For example, in order to leave the moon (which has a much smaller mass, and gravitational pull, than the earth), you wouldn't need as great an escape velocity. Now imagine a body whose mass is so great, even something traveling at the speed of light couldn't escape. That body would appear as a black hole, because even light couldn't escape from it. So, contrary to your cousin, a black hole is not capable of overcoming the speed of light. Nothing is.

- Bill
(Edited by William Dwyer
on 12/26, 6:16pm)

Post 58

Tuesday, December 27, 2005 - 9:07am

http://xxx.soton.ac.uk/find/astro-ph/1/superluminal+motion/0/0/0/all+years/8/0

http://www.aei-potsdam.mpg.de/~mpoessel/Physik/FTL/tunnelingftl.html

(Edited by Robert Davison on 12/27, 9:08am)

Post 59

Tuesday, December 27, 2005 - 11:25am