Showing posts with label The Bias Planet. Show all posts
Showing posts with label The Bias Planet. Show all posts

2022-06-12

42: Secret of Zeno's Paradox and Countermeasures Against Tricks

<The previous article in this series | The table of contents of this series | The next article in this series>

The real trick by which you tend to be deceived in Zeno's paradox is not being prevalently talked. Let us learn how to resist any trick.

Topics


About: truth

The table of contents of this article


Starting Context



Target Context


  • The reader will understand the real trick of Zeno's paradox and how to resist any trick.

Orientation


There is an article on harmful rhetoric.


Main Body

Stage Direction
Here is Special-Student-7 in a room in an old rather isolated house surrounded by some mountains in Japan.


1: Zeno's Paradox


Special-Student-7-Hypothesizer
Zeno's paradox claims like this.

Running Achilles will never catch up a turtle that is crawling ahead of him, because when Achilles reaches the present location of the turtle, the turtle will be already ahead of the location; when Achilles reaches the new location of the turtle, the turtle will be already ahead of the location; when Achilles ~, and so on, which will never end.

Special-Student-7-Rebutter
Ah.

Special-Student-7-Hypothesizer
"Ah" what?

Special-Student-7-Rebutter
Were you taken in by that?

Special-Student-7-Hypothesizer
I was not exactly taken in, because it is obviously wrong: Achilles can undoubtedly catch up the turtle. However, I must confess that it took certain time until I understood the trick.


2: The Prevalent Explanation


Special-Student-7-Hypothesizer
The prevalent explanation is, in short, that the time taken in Achilles's catching up the turtle converges.

In long, for the initial distance between Achilles and the turtle, l, the velocity of Achilles, \(v_A\), and the velocity of the turtle, \(v_t\), the time taken in Achilles's reaching the present turtle location is \(t_0 = v_A^{-1} l\), the distance covered by the turtle in \(t_0\) is \(v_t t_0\); the time taken in Achilles's reaching the new turtle location is \(t_1 = v_A^{-1} v_t t_0 = v_A^{-1} v_t v_A^{-1} l = l v_A^{-1} v_A^{-1} v_t\), the distance covered by the turtle in \(t_1\) is \(v_t t_1\); generally, \(t_i = l v_A^{-1} v_A^{-i} v_t^{i}\); so, the time taken in Achilles's catching up the turtle is \(t = \sum_{i = 0, 1, ..., \infty} t_i = l v_A^{-1} (1 + v_A^{-1} v_t + v_A^{-2} v_t^2 + . . . ) = l v_A^{-1} (1 - v_A^{-1} v_t)^{-1}\), which is not the infinity.

For example, supposing that \(l = 1\), \(v_A = 1\), and \(v_t = 0.1\), \(t = 1 + 0.1 + 0.01 + . . . = 1.11 . . . \), which obviously does not go over even 1.2.


3: Why Did You Not Bother to Do the Calculation?


Special-Student-7-Hypothesizer
In fact, you did not need to know the concept of convergence, in order to break the paradox.

You could just do the calculation, then, you would have noticed that the time did not go to the infinity.

Why did you not just bother? . . . You should repent.


4: The Real Trick


Special-Student-7-Hypothesizer
Anyway, why was the paradox so successful?

The reason why you were tricked is not that you did not know that an infinite series did not necessarily go to the infinity, I guess.

The reason is that you confused 2 times: the time taken in saying "when Achilles reaches the present location of the turtle, the turtle will be already ahead of the location; when Achilles ~" and the time taken in Achilles's catching up the turtle.

What Zeno really proved is just that you will never finish saying "when Achilles reaches the present location of the turtle, the turtle will be already ahead of the location; when Achilles ~", not that Achilles will never catch up the turtle.

To think in one's right mind, it is kid's stuff.

It takes only several seconds to say "Ten years have passed", but it takes ten years for ten years to pass; the 2 times are obviously different.

Special-Student-7-Rebutter
Well, people may not have exactly confused the 2 times, but at least seem to have had a misconception that there was a kind of relationship between the 2 times in which if one of the 2 times was the infinity, also the other would be the infinity.

Special-Student-7-Hypothesizer
It is obviously a misconception: it takes only several seconds to say "An infinite time has passed", but it takes an infinite time for an infinite time to pass.

If they had not exactly confused the 2 times, at least they had "identified" the 2 times with respect to being infinite or non-infinite.

Anyway, as a proof of that the confusion or identification of the 2 times is the real reason, this "paradox" will not be as successful as Zeno's: "In order for Achilles to measure the distance from him to the turtle (which is not moving in this case), Achilles has to go to the half point, measuring the distance; Achilles has to go to the half point of the rest distance, measuring and adding the distance; Achilles ~; and so on. So, the distance is the infinity.".

Special-Student-7-Rebutter
As many people would not be tricked by it as by Zeno's.

Special-Student-7-Hypothesizer
If the issue was about convergence of infinite series, you would be tricked by it likewise by Zeno's.

You would not be tricked by it because you would not confuse (or identify) the time taken in saying "Achilles has to go to the half point measuring the distance; Achilles ~" with the distance.

Special-Student-7-Rebutter
You mean, people may be likely to confuse or identify a time with another time, but they are far less likely to confuse or identify a time with a distance.

Special-Student-7-Hypothesizer
I suspect also that Zeno's paradox was so successful because it was about time; I mean, people will less easily confuse or identify a distance with another distance.

Special-Student-7-Rebutter
It may be so; people are rather insensitive to time.


5: We Should Learn from the Example, How to Resist Any Trick


Special-Student-7-Hypothesizer
Now we know how we were tricked by Zeno's paradox.

But it is a waste of opportunity to stop there: we should learn how to reject any trick, with the example as a teaching material.


6: Logically Speaking, It Is Simple


Special-Student-7-Hypothesizer
In order to reject any trick, logically speaking, it is simple: accept only true propositions and take only valid deductions. Then, you cannot be deceived by any trick.

Special-Student-7-Rebutter
Certainly, but it will be "easy to be said but hard to be done".

Special-Student-7-Hypothesizer
I guess so, so, we have to adopt some practical countermeasures.


7: Any Trick Is About Attention


Special-Student-7-Hypothesizer
As a grounding, we should know that any trick is about attention.

The trickster diverts your attention from the trick; very often, the trick itself is not so complex to be difficult to be penetrated, once a due attention is directed to it; it is that the trick is hidden from your attention.

Special-Student-7-Rebutter
The trickster may be you, in fact.

Special-Student-7-Hypothesizer
Yes. It is called 'self-deception', which may be intentional as a rationalization or unintentional as an innocent mistake.

Anyway, the countermeasure should be to distribute your attention evenly, especially to things being neglected by you.

Special-Student-7-Rebutter
You cannot catch out the trick by very closely watching what the magician is inviting you to watch, because that is exactly the magician's ploy.

Special-Student-7-Hypothesizer
In the case of Zeno's paradox, you are invited into the details of "when Achilles reaches the present location of the turtle, the turtle will be already ahead of the location; when Achilles ~", and you are impressed by the impeccability and the cleverness of the details, with your attention being fixated on the presented details.

Inundating your attention with some innocent details is a usual ploy: as your attention capacity is limited, occupying your attention with the details prevents your attention from noticing the trick.

Of course, it is not that details are bad or unnecessary; the trick can be revealed by checking the details around the trick, but your attentions is being kept far away to attend other details.

Special-Student-7-Rebutter
Sure; we should distribute our attention evenly, but that is very difficult to be really executed.

Special-Student-7-Hypothesizer
Certainly, it will be impossible to be executed perfectly. But we should be able to execute it better.

Special-Student-7-Rebutter
Even only being aware that any trick is about attention will make a difference, but being equipped with some tactics will be better.

Special-Student-7-Hypothesizer
That is the reason why this article does not end here.


8: Still We Tend to Fall into Traps, so We Should Beware of Usual Types of Traps


Special-Student-7-Hypothesizer
While the trap can be different for each trick, there are some usual types of traps, and knowing and bewaring of such types will be helpful.


8-1: Concept Replacement


Special-Student-7-Hypothesizer
A usual type of traps is to surreptitiously replace a concept with another concept.

That means, we had been talking about a concept, but without noticed, we have been tricked to be talking about another concept.

In the case of Zeno's paradox, the paradox was really talking about 'the time taken in your saying "When Achilles reaches the present location of the turtle, the turtle will be already ahead of the location; when Achilles ~"', but the conclusion is about 'the time taken in Achilles's catching up the turtle'.

Special-Student-7-Rebutter
As we talked before, such replacements seem to be performed frequently via careless identifications of the concepts instead of via mere confusions of the concepts.

Special-Student-7-Hypothesizer
"identification" means that although the 2 concepts are known to not be exactly the same, we consent to talk in terms of the alternative concept, supposing that it will not make any difference for the immediate argument; a very dangerous move, I say.

You know, it is hazardous to casually identify concepts, because usually, you cannot be sure that the concepts are interchangeable for the sake of the argument, until the argument has been completed.

Special-Student-7-Rebutter
If you consent to a concepts identification, you will have to be always watching whether the identification is still valid in the argument, but you will not probably do that, because than doing such a thing, doing without the identification will be far easier.

Special-Student-7-Hypothesizer
So, it will be a sound principle that you do not consent to the identification in the first place.

Anyway, the hotbed of concepts confusions is to use the same term for multiple concepts.

While the term is brought forth in front of your attention for each appearance, as the relation between the term and the concept associated with is not stable, you can be easily tricked to switch to be talking about another concept.

The concept associated with for the term is believed to be determined by the context, but the context does not consist only of the explicit concept but also of the implicit context like the person's knowledge and expectation.

Special-Student-7-Rebutter
"expectation" is especially a vital factor: if the person is interested in a concept, he or she will easily associate the term with the concept.

Special-Student-7-Hypothesizer
So, as the trickster leads your interest, your association is manipulated.

Using the same term for multiple concepts includes omitting due qualifications: when 2 concepts have to be differentiated by some qualifications, if the qualifications are stripped off, the 2 concepts are being represented by the same term.

In the case of Zeno's paradox, saying just "the time" blurs the distinction between the concept of 'the time taken in your saying "When Achilles reaches the present location of the turtle, the turtle will be already ahead of the location; when Achilles ~"' and the concept of 'the time taken in Achilles's catching up the turtle', and "the time" tends to be mistakenly associated with the latter, which you are interested in.

Special-Student-7-Rebutter
The paradox does not even use the term, 'time'.

Special-Student-7-Hypothesizer
It uses "never", which is inevitably about time, but anyway, "never" itself is also ambiguous, because "never" what? You "never" finish saying "When Achilles reaches the present location of the turtle, ~"?, Achilles "never" catch up the turtle?, or what?

Using "never" is logically the same with using "the time taken is more than the infinity", but it seems to make you more vulnerable.

Special-Student-7-Rebutter
Why is that?

Special-Student-7-Hypothesizer
Well, because "never" is harder to be qualified, I guess.

Special-Student-7-Rebutter
What do you mean by "harder to be qualified"?

Special-Student-7-Hypothesizer
When you are told "never", you will usually not ask "Which never?".

Special-Student-7-Rebutter
Is "Which never?" grammatically valid?

Special-Student-7-Hypothesizer
It is not, which is the point: you are discouraged against asking the due question because it is grammatically invalid.

Special-Student-7-Rebutter
So, should we prefer nouns over adverbs?

Special-Student-7-Hypothesizer
I think so. Look, you may think that you can choose any expression if it is logically the same, but the choice of expression makes a difference because the issue is attention.

When 'time' is used, you are more likely to ask "Which time?" or "Time taken in what?" to be more deliberately expressed.

Special-Student-7-Rebutter
It is quite likely.

Special-Student-7-Hypothesizer
And while "never" means nothing but 'the time taken is more than the infinity' and you have to confirm that the time is really more than the infinity in order to be able to claim "never", when "never" is used, you are more likely to do without really calculating the time.

In the case of Zeno's paradox, the time taken in your saying "When Achilles reaches the present location of the turtle, the turtle will be already ahead of the location; when Achilles ~" is certainly infinite without any minute calculation, but by doing the calculation, you are likely to notice that you are not talking about the time taken in Achilles's catching up the turtle.

Generally speaking, doing appropriate quantification is helpful.


8-2: Some Traps Concerning Quantification


Special-Student-7-Rebutter
"appropriate quantification" will be helpful, but we should be aware that sometimes, quantification is the trap.

Special-Student-7-Hypothesizer
I did not say that any quantification was good; any inappropriate quantification is more harmful than non-quantification.

Special-Student-7-Rebutter
What is "inappropriate quantification"?

Special-Student-7-Hypothesizer
Any inappropriate quantification is to quantify something with an inappropriate measure for the purpose.

For example, humans may be quantified by weight, but weight may not be the right measure for them to be evaluated with, unless they are sumo wrestlers or being sold as meat.

Special-Student-7-Rebutter
Especially, statistics can be traps for many people.

Special-Student-7-Hypothesizer
A typical trap of statistics is the biased population: by tampering the population deliberately or inadvertently, the statistic can be significantly swayed.

It is important to always check the population when faced with any statistic.

Special-Student-7-Rebutter
There is also the matter of accuracy of quantification.

Special-Student-7-Hypothesizer
Yes. The number may be just fairly wrong, while some people tend to suppose that the number should be accurate just because it is a number,


8-3: Unbalanced Citation


Special-Student-7-Hypothesizer
This is a plain example that any trick is about attention.

You cite only what are convenient for you, for example, examples that conform to your claim or some facts that you have exerted much effort, and you insist that your claim is true or you deserve specific (additional) reward for the effort, while there are really also examples that refute your claim or you have already reaped the reward of the effort enough.

Special-Student-7-Rebutter
Those both examples are quite prevalent among Earthians.

Special-Student-7-Hypothesizer
While the former example is explained in an another article, let us talk about the latter example.

After you have taken the effort and have reaped the reward explicitly or implicitly, you tend to keep bringing up only the effort and demanding more reward again and again, saying "Have you forgotten my effort? You, ungrateful creature!"

Special-Student-7-Rebutter
It is more often "implicitly", which is the reason why "Nothing is more costly than being given free.". As we have not decisively settled the transaction, the "giver" endlessly keeps demanding more.

Special-Student-7-Hypothesizer
In the 1st place, while the "giver" is assuming that his or her effort should be rewarded by me, I am not obliged to pay for his or her self-satisfying effort even if I feel it appropriate to pay only as much as the benefit I have received as the result of the effort if any.

Special-Student-7-Rebutter
If you want a reward from your deed, you have to obtain an agreement that you be rewarded how before you do the deed; otherwise, you have no right to demand any reward afterward.


8-4: Inadvertently Accepting an Implicit Premise


Special-Student-7-Hypothesizer
Another usual type of traps is to inadvertently accept an implicit premise.

Special-Student-7-Rebutter
Ah, a tricky one.

Special-Student-7-Hypothesizer
Yes, because it is very difficult to completely reject the trap.

Again, it is about attention: without directing your attention to the implicit premise, you cannot check the premise, but directing your attention to the implicit premise means making the implicit premise explicit, so, you have to make all the premises explicit, which is practically very difficult.

Special-Student-7-Rebutter
Again, it is about making it better, not about making it complete; a detrimental attitude is to despair that you cannot make it complete, so you just give it up completely.

Special-Student-7-Hypothesizer
When you accept an implicit premise, you do so not necessarily because the premise seems obvious, but because you do not direct your attention to it. If you ask yourself whether you should accept the premise, you may rather swiftly reject it.

And a typical case seems to be that you fleetingly wonder about an implicit premise, but let the trickster go ahead, thinking that you can go back to it later, but forget about it, with your attention being distracted to other things by the trickster.

Special-Student-7-Rebutter
It seems to be a prevalent vice to be too confident of your ability to command your attention. People seem to tend to assume that they can easily command their attention at their will because it is their own attention, but it is not so.

Special-Student-7-Hypothesizer
There are some usual types of implicit premises and knowing them will be helpful for noticing faulty implicit premises.


8-4-1: Faulty Dichotomy (or Multichotomy)


Special-Student-7-Hypothesizer
A typical type of faulty implicit premises is faulty dichotomy (or multichotomy).

It is, "(A or B.) Not A. So B." where "(~)" means that it is implicitly supposed or inconspicuously expressed as not to draw attention.

Special-Student-7-Rebutter
But is it really "A or B."? Is it not a possibility of C, D, or whatever?

Special-Student-7-Hypothesizer
If we are asked so, we are likely to rather promptly notice that there are other possibilities, but we have to ask ourselves so.

Special-Student-7-Rebutter
It may be "(A, B, or C)" in fact.

Special-Student-7-Hypothesizer
Yes: that is the reason why I said "multichotomy", although I cannot find such a word in any Biasian dictionary, I do not understand why.

Anyway, faulty dichotomy is prevalent also in self-deception: "(I should get that woman or I should die.) I cannot get that woman. So, I should die.". . . . That is a pretty too-simplistic dichotomy, I say!

Special-Student-7-Rebutter
It is prevalently seen phenomena that people are fixated on choosing only from some fixed ways; you should ask "Is there not another way?".


8-4-2: Faulty Existence


Special-Student-7-Hypothesizer
Usually, the argument is constructed based on the presupposed existence of something.

Special-Student-7-Rebutter
Yes. When a proposition is presupposed, the entities that appear in the proposition are presupposed to exist.

Special-Student-7-Hypothesizer
It seems more difficult to doubt the existences of the entities than to doubt just the proposition.

Special-Student-7-Rebutter
It is more difficult because the existences are implicitly presupposed.

Special-Student-7-Hypothesizer
Yes. When a proposition is "A is B.", it is really "(A exists.) (B exists.) A is B, by the way."

We cannot check implicit presuppositions unless we make them explicit.

I notice that a type of entities that tend to be faultily presupposed to exist is ability.

Special-Student-7-Rebutter
Besides being implicitly presupposed, the existence of an ability is frequently difficult to be refuted.

Special-Student-7-Hypothesizer
That is because we cannot refute the existence of the ability just because the ability is not exerted this time or even has never been exerted.

In order to exactly refute the existence of the ability, we will have to prove that the ability is physically impossible, which is frequently difficult, especially for human abilities.

In the ideal of so-called "democracy", majority are expected to respect interests of minority, but it is preposterous to presuppose the existence of that ability in majority.

Majority have the power to decide things as to maximize only their profits, and can they refrain from doing so, in order to respect interests of minority? . . . It is nobleness, and I know that there exists nobleness,even among Biasians, but I know that nobleness is very rare, found in only a tiny percentage of people. It is preposterous to assume such nobleness in majority.

Special-Student-7-Rebutter
That is a reasonable estimation, but is not an exact proof.

Special-Student-7-Hypothesizer
So, the preposterous ideal of "democracy" keeps being preserved.

Special-Student-7-Rebutter
It should not really be about the exact refutation of the existence of the ability, but about unwiseness of relying on such an at-least-unlikely and never-demonstrated ability, even if it exists.

Special-Student-7-Hypothesizer
It is a widely seen harm that people just wish the existence of an ability and pretend as though the ability was being exerted, which is exactly how majoritarianism is being defended.

Special-Student-7-Rebutter
As I said, whether the ability exists or not, as far as the ability is not being exerted in fact, at least reliably, we should take measures based on the assumption that the ability probably will not be exerted.


8-4-3: Some Widely-Assumed, Selfish, Ludicrous, Implicit Propositions


Special-Student-7-Hypothesizer
There are some selfish implicit propositions, which are ludicrous, but are widely-assumed nevertheless.

For example, "What I believe to be true is true.".

Special-Student-7-Rebutter
Ah, I see many arguments in which a party claims something to be true just because the party believes it to be true.

Special-Student-7-Hypothesizer
Or "What I wish to be true is true."

Special-Student-7-Rebutter
More ludicrous, but not particularly less seen.

Special-Student-7-Hypothesizer
Sometimes, it takes a form like "If it is true, it will be troublesome, so, it is not true.".

Special-Student-7-Rebutter
What a selfish assumption!

Special-Student-7-Hypothesizer
And there are some anthropocentric propositions adopted by even many educated people on the Bias plant, like "What can't be measured by humans don't exist.", "What can't be known to humans don't exist.", "What cannot be defined by humans don't exist.", "What cannot be done calculation on by humans don't exist.".


8-5: Illegitimately Generalizing a Proposition


Special-Student-7-Hypothesizer
Another usual type of traps is to illegitimately generalize a proposition.

Special-Student-7-Rebutter
Is it not just an induction?

Special-Student-7-Hypothesizer
Any induction is fine only if it is presented as a hypothesis, and it requires being examined whether it conforms to all the known cases, even if it is not logically proved.

"to illegitimately generalize a proposition" means to claim the generalization to be a truth without any legitimate proof, usually without even mentioning the existence of the generalization.

Special-Student-7-Rebutter
If the proposition is presented explicitly, the trap seems rather easy to detect, if we are rigidly logically-minded.

Special-Student-7-Hypothesizer
I guess so, but anyway, the practice of this type of traps is prevalent, and most Biasians are not rigidly logically-minded.

Special-Student-7-Rebutter
If the proposition is implicit, even a rigidly logically-minded person can be tricked.

Special-Student-7-Hypothesizer
Yes. Being implicit means that our attention is not given at it, and what is not being attended to can be easily tampered, a general mechanism of tricks.

Even if we are rather rigidly logically-minded, we sometimes could be tricked, so, we should remind ourselves the basics of propositions.

We should always regard any proposition as an inseparable combination of a set of some preconditions and a conclusion, like "If ~, then ~.".

Special-Student-7-Rebutter
Is there always a precondition?

Special-Student-7-Hypothesizer
There might not be in rare cases, but we can think that there is the always-true precondition even in those cases.

My point is that we should always assume that there is the set of preconditions, because you tend to forget it and forgetting it is detrimental.

Again, it is about attention: it is important to not let your attention absorbed solely into the conclusion with the set of preconditions left out of the scope of your attention.

"to illegitimately generalize a proposition" means to abuse the conclusion with the set of preconditions loosened or even completely forgotten.

It is different from accepting implicit propositions, because the preconditions are not particularly being accepted, but the necessity for the preconditions is being forgotten.


8-6: Rushingly Accepting a Spurious Deduction


Special-Student-7-Hypothesizer
Another usual type of traps is to rushingly accept a spurious deduction.

Special-Student-7-Rebutter
You mean, the deduction is just wrong?

Special-Student-7-Hypothesizer
Yes. You just did not check the deduction enough or even at all.

Special-Student-7-Rebutter
Is it not just that you were just poor-minded?

Special-Student-7-Hypothesizer
Well, you may say so . . ., but there is a usual tactic that entices you to skip checking the deduction.

Special-Student-7-Rebutter
What is that?

Special-Student-7-Hypothesizer
The usual tactic shows a meticulous and correct proof of a proposition and says like "Also this is true while I entrust you to prove it.".

Special-Student-7-Rebutter
And you do not bother to prove it, probably.

Special-Student-7-Hypothesizer
As the trickster has done the previous proof impeccably, you believe that the new proposition should have been proved by the trickster as well.

Special-Student-7-Rebutter
If the trickster really says "I entrust you to prove it" explicitly, he or she is rather conscientious, but usually, the trickster does not, and you just fill the gap.

Special-Student-7-Hypothesizer
The same trick is prevalently used in story-telling: the author shows a meticulous description of a part of an imaginary world, and the reader believes that the world should be filled with details all over, while the world is really almost empty, of course.

Special-Student-7-Rebutter
A TV show shows a few rooms in a spaceship, and viewers imagine the spaceship full of rooms.

Special-Student-7-Hypothesizer
The tactic can be more nasty than you imagine, because human brains are wired to unconsciously interpolate wishful imaginations to fill gaps, but knowing the existence of the tactic will be helpful.


9: In Any Case, Your Laziness, a.k.a. Labor-Saving Is Being Taken Advantage of


Special-Student-7-Hypothesizer
While there are various types of traps, you fall into one because of your laziness.

In the case of concept replacement, as you grudge the effort of using a strict terminology (in which, each term corresponds to a definite concept), you allow a term to mean multiple concepts, so, you allow a concept to be surreptitiously replaced with another concept in virtue of being represented by the same term.

In the case of implicit premise acceptance, as you grudge the effort of making all the premises explicit, you allow the spurious premise to slip into the argument.

In the case of proposition generalization, as you grudge the effort of checking the fulfillment of all the preconditions each time, you allow the conclusion to be abused.

In the case of spurious deduction acceptance, as you grudge the effort of strictly checking the deduction, you allow the deduction to go through.

Special-Student-7-Rebutter
Labor-saving is fine while it is skipping doing unnecessary things, but most people cannot refrain from also skipping doing necessary things.

Special-Student-7-Hypothesizer
Wanting to save one's energy is a major animal instinct, but containing such urge should be a major human distinction.


10: The Countermeasures



10-1: The Principle: State Explicitly and Check Diligently


Special-Student-7-Hypothesizer
To sum up, the principle for the countermeasures is to state any proposition explicitly and check any deduction diligently.

Special-Student-7-Rebutter
A principle which most Earthians cannot or will not follow, I guess.

Special-Student-7-Hypothesizer
Which is the case?

Special-Student-7-Rebutter
I do not know whether their will is too weak to resist the animal instinct or their will is adamant that they should be allowed to follow the animal instinct.

Special-Student-7-Hypothesizer
I find that a useful tactic to counter an animal instinct by human will is to form a habit, which can be formed by human will.

If you think that you can invoke the principle only when it is required, probably, you will not notice the occasion when it is required.

Special-Student-7-Rebutter
But as you cannot practically always fully employ the principle, some dynamics should be required.

Special-Student-7-Hypothesizer
Of course. I think that there is a difference between that you basically employ the principle, but loosen the principle occasionally and that you basically does not care the principle, but intent (but probably fail) to employ the principle occasionally.

Well, while the principle should be enough if executed perfectly, I admit that it is hard to be executed perfectly, so, let us know some effective techniques.


10-2: A Technique: Rephrase the Proposition


Special-Student-7-Hypothesizer
You may snub rephrasing, regarding it as a waste, because the new phrase should mean nothing new, but it often makes a critical difference.

If you have managed to rephrase "Achilles never catch up the turtle." to "The time taken in Achilles's catching up the turtle is more than infinity.", you will be already very near breaking the trick.

Special-Student-7-Rebutter
Is there some guidance for what should be the new expression?

Special-Student-7-Hypothesizer
Expressing concepts, at least core concepts, in nouns will be beneficial.

That is because that makes the concepts more easy to be scrutinized.

Special-Student-7-Rebutter
Especially, nominalization seems to encourage quantification.

Special-Student-7-Hypothesizer
Yes. Being just "fast" is just a matter of impression, and introducing 'speed' encourages us to ask "What speed?", "What km/h"?

Special-Student-7-Rebutter
We should know that human impressions are hugely unreliable.

Special-Student-7-Hypothesizer
I can think of some other types of rephrasing like negation-affirmation changes and subject-object changes.

Special-Student-7-Rebutter
Are "subject-object changes" passive-active changes?

Special-Student-7-Hypothesizer
Not necessarily: "A hit B." can become not only "B is hit by A." but also "B got a punch from A." or "B enjoyed a punch by A.".

Special-Student-7-Rebutter
Ah, B may be a masochist.

Special-Student-7-Hypothesizer
It is one of our purposes to escape prejudice like "B must be regrettably hit.", which "A hit B." should not necessarily connote.


10-3: A Technique: Thinking of Extreme Cases


Special-Student-7-Hypothesizer
A useful check for any proposition is to think of extreme cases.

That is because a proposition tends to show gapes in extreme cases.

Special-Student-7-Rebutter
Many Earthians seem to try to get away with the proposition by claiming that such gapes are just exceptions.

Special-Student-7-Hypothesizer
I say, any proposition with any exception is meaningless, because if there is an exception, any concerned case can be an exception, so, nothing can be claimed by the proposition.

Such a selfish ruse as opportunistically dismissing only inconvenient cases as exceptions is never allowed.

If there are some exceptions, the exceptions must have been incorporated into the proposition as preconditions; that is what you must do.

For example, if you support the proposition, "People must obey any evil law.", you should think about a case that a law orders you to kill your baby, for example.

Special-Student-7-Rebutter
Why does the law order that?

Special-Student-7-Hypothesizer
Who knows? It is an evil law; perhaps, because the baby is not eugenic, is immature, or has a little crooked little toe.

Anyway, will you obey the law? If not, you must not support the proposition.

Special-Student-7-Rebutter
While there are some people who nonchalantly claim that you must lawfully try to repeal the law instead of disobeying the law, . . .

Special-Student-7-Hypothesizer
you are ordered to kill your baby right now.

You are not allowed to claim that this case is an exception; if this case is your exception, any case can be someone's exception.

Special-Student-7-Rebutter
I do not guess that many can really support that proposition.

Special-Student-7-Hypothesizer
Brandishing such a rough proposition is irresponsible; what we are supposed to do is to argue on what conditions any law must be obeyed.

Anyway, if you are familiar with software engineering, the check is like a borderline test, which is efficient in finding out bugs.


10-4: A Technique: Making a Wise, Typically Whole and Static Visualization


Special-Student-7-Hypothesizer
Making a visualization sounds a trite technique, but it should be useful if done wisely.

I say "wisely" because 'what kind of visualization?' is the issue.

For example, a vivid picture of an instant at which Achilles is perspiring on his forehead with his teeth clenched is a kind of visualization, but is not particularly useful in breaking the paradox.

Special-Student-7-Rebutter
We are talking about a graph, not about a picture, at least in that case.

Special-Student-7-Hypothesizer
But in another case, a picture may be useful.

So, just saying "do a visualization" is easy, but choosing a right kind of visualization is not necessarily easy.

Special-Student-7-Rebutter
Are there some criteria for being a right kind of visualization?

Special-Student-7-Hypothesizer
Being whole and static, perhaps.

Special-Student-7-Rebutter
What does that mean? The picture of perspiring Achilles is static.

Special-Student-7-Hypothesizer
But is not whole; I mean, it is only of an instant (a part), not of the whole of the concerned phenomenon.

If you gather up such pictures and make them an animation, it is a kind of visualization, but is not static.

Special-Student-7-Rebutter
Is animation bad?

Special-Student-7-Hypothesizer
I am not particularly an enemy of animation, but you tend to be easily deceived by an animation.

For example, in a baseball animation, a pitcher pitches, the ball comes, the batter begin to remember old days in which he was ridiculed by fellow children as a hacker and he practiced swings in front of a red giant setting sun or under a starry sky and he was still ridiculed and he practiced more and . . ., before the ball reaches him in zero point what second, and you accept such absurdity and even shed tear.

Special-Student-7-Rebutter
Humans are fairly blurry about time.

Special-Student-7-Hypothesizer
So, it had better be static in order for you not to be deceived.

A typical wise visualization is the world lines of the concerned objects.

If you had just drawn the world lines of Achilles and the turtle, you would have easily seen what the paradox was saying: it was saying of increasingly short line segments whose time coordinates did not reach the catch-up time at all, to say nothing of infinity.


References


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2021-11-28

6: "cogito, ergo sum" Is Childish. Then, What Are Really Sure?

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Assuming we know something for sure while we do not is really harmful. On the other hand, any contradictory claim is know to be false for sure.

Topics


About: truth

The table of contents of this article


Starting Context



Target Context


  • The reader will know what are known for sure as well as what are not really known for sure.

Orientation


There are some articles on truthfulness (here, etc.).

There is an article on the reality, observations, and interpretations of them.


Main Body

Stage Direction
Here is Special-Student-7 in a room in an old rather isolated house surrounded by some mountains in Japan.


1: An Impractical Ideal, but What About Mathematics?


Special-Student-7-Hypothesizer
Building a theory based on only what are known for sure is an enchanting ideal, but is really impractical.

Special-Student-7-Rebutter
Is it?

Special-Student-7-Hypothesizer
What part are you questioning? The "enchanting" part or the "impractical" part?

Special-Student-7-Rebutter
The "impractical" part.

Special-Student-7-Hypothesizer
Well, what are known really for sure are quite limited, so, not much can be built on them.

Special-Student-7-Rebutter
What about mathematics?

Special-Student-7-Hypothesizer
Mathematics is special in its not really dealing with the reality.

For example, when it talks about a straight line in a Euclidean space, in fact, there is no such straight line in the reality, as the universe itself is not Euclidean. But it is fine for mathematics: mathematics is not saying that such a straight line exists; it is discussing how such a straight line would be if it existed.

Special-Student-7-Rebutter
So, is mathematics built on what are known for sure, or not?

Special-Student-7-Hypothesizer
It is, basically in a way, I guess. It is based on definitions, which are known for sure. Any straight line is known for sure to be as has been defined; whether such a straight line exists in the reality is not the issue.

Special-Student-7-Rebutter
So, mathematics is not built on hypotheses?

Special-Student-7-Hypothesizer
Definition is different from hypothesis: a hypothesis may turn out to be false, but any definition does not turn out to be false, although it may turn out to correspond to nothing in the reality.

Special-Student-7-Rebutter
What about an ill-defined definition?

Special-Student-7-Hypothesizer
Any ill-defined "definition" is not really any definition: it is a bogus definition; I am talking about real definitions. So, a supposed-to-be-definition may turn out to be not a definition, but no real definition turns out to be "false".

Special-Student-7-Rebutter
Fair enough.

Special-Student-7-Hypothesizer
So, a theory can be built as something that discusses relationships among definitions, but i t may have nothing to do with the reality.

Special-Student-7-Rebutter
And is mathematics that?

Special-Student-7-Hypothesizer
Theoretically speaking, a theory can have nothing to do with the reality, but practically speaking, such a theory will be probably useless. Definitions in mathematics are chosen to be applicable to the reality at least approximately. The definition of straight line in Euclidean space is useful as it is approximately applicable to the reality.


2: "Cogito, Ergo Sum"?


Special-Student-7-Hypothesizer
There was a Biasian who said "cogito, ergo sum", but it is quite childish.

Special-Student-7-Rebutter
I am mot sure what he meant by that, although I am sure that it is a failure as a joke.

Special-Student-7-Hypothesizer
'Darth Vader thinks, therefor Darth Vader is'?

Special-Student-7-Rebutter
Does Darth Vader think?

Special-Student-7-Hypothesizer
He is thinking in the movies.

Special-Student-7-Rebutter
Mr. Descartes does not seem to have been talking about such a kind of thinking.

Special-Student-7-Hypothesizer
But the problem is that he could not know for sure that he himself was not thinking in that kind of thinking.

Special-Student-7-Rebutter
Could he not?

Special-Student-7-Hypothesizer
I do not guess that he could. If he had really managed to do so, he should have explained how, because that is the point.

Special-Student-7-Rebutter
It seems just that Mr. Descartes could not imagine that he was thinking in a movie.

Special-Student-7-Hypothesizer
That is simply his problem. That is about that he had a limited imaginative faculty.

Special-Student-7-Rebutter
Well, Darth Vader "is", in a way.

Special-Student-7-Hypothesizer
Certainly, he "is", as a fictional character.

Then, "am" "I" not a fictional character?

Special-Student-7-Rebutter
That is the reason why I said that I was not sure what was meant by "cogito, ergo sum": just saying "I am" means nothing; "I am" as what sort of existence is the issue.

Special-Student-7-Hypothesizer
I guess that he thought he "was" a real being, not a manga character.

Special-Student-7-Rebutter
That is just his personal belief, I have to say.


3: I Think, Therefore Something Is


Special-Student-7-Hypothesizer
"I" may be a manga character, but then, there must be someone who wrote the manga work.

Special-Student-7-Rebutter
But of course, the manga author may be a manga character.

Special-Student-7-Hypothesizer
But there must be someone who wrote the manga work in which the manga author appears, and so on.

So, there must be a real someone somewhere.

Special-Student-7-Rebutter
I wonder. Can the sequence not be infinite?

Special-Student-7-Hypothesizer
Well . . ., I do not think so, because that would be the same with that just nobody wrote the manga work, I mean, at least, somehow, the sequence must converge into a real author.

Special-Student-7-Rebutter
Probably, although I am not really sure about such thing as a sequence converging into an author.

Anyway, that real someone may not be a human, of course?

Special-Student-7-Hypothesizer
He or she may not be a human, a Klingon, a god, or whoever, and of course, it may not be appropriate to call the someone "He or she", or it may be inappropriate to call the someone "someone". I should rather call it 'something'.

'I think, therefore something is', that is what I am sure of.


4: Which Means, the Universe Is?


Special-Student-7-Hypothesizer
Which mean, the Universe is.

Special-Student-7-Rebutter
Does it so?

Special-Student-7-Hypothesizer
I think so, because otherwise, where would the something be?

Special-Student-7-Rebutter
Well, should I say 'nowhere'?

Special-Student-7-Hypothesizer
But 'Something is nowhere.' means nothing but 'Something is not.'

Special-Student-7-Rebutter
That sounds bad word play . . ., in the first place, what do you mean by "the Universe".

Special-Student-7-Hypothesizer
The Universe is . . . the container of all the things that really exist.

Special-Student-7-Rebutter
An unsatisfactory answer, considering the possibility of other universes.

Special-Student-7-Hypothesizer
The Universe is . . . the container of all the things that really exist in the Universe.

Special-Student-7-Rebutter
You know, that is a vicious circle, with "the Universe" used in the explanation of "the Universe".

Special-Student-7-Hypothesizer
Well, distinguishing this Universe from the other universes is a different issue from whether this Universe exists. An inferior bug crawling in a corner of this Universe may know that at least this Universe exists but does not know whether other universes exist or how to distinguish this Universe from other universes; regard me as the bug.

In fact, I guess that each universe is a connected manifold, but of course, I cannot say for sure that this Universe is a manifold.

Special-Student-7-Rebutter
Saying that this Universe is a container is not meaningful, without explaining the container as a certain physical existence, because you can whimsically imagine any arbitrary conceptional container.

There may be only the single manga author in the world and there may not be any physical container that contains the manga author, but you can imagine the conceptional container that contains the manga author and claim that the Universe exists; in that sense, the Universe certainly "is".

Special-Student-7-Hypothesizer
This may be different from knowing absolutely for sure, but most probably, the manga author is not a single particle, because any single particle does not seem to be able to create any manga work.

Special-Student-7-Rebutter
"different"? Yes. "most probably"? I agree.

I can imagine the manga work only as an arrangement of some particles, while I humbly admit that that may be only because of my limited imaginative faculty. How can the manga work be conceived inside a single particle? I cannot imagine.

Special-Student-7-Hypothesizer
Then, as the manga work exists, most probably, some particles exist, and they can be arranged to represent the manga work, and the stage on which such an arrangement can be done is the Universe.

I think that I can most safely assume the existence of such a physical Universe.


5: Hypotheses Are Demanded, but Any Hypothesis Must Not Be Mistook for an Known Truth


Special-Student-7-Hypothesizer
Thus, usually, we cannot build a theory based on only what are known for sure.

So, hypotheses are demanded and are really OK.

But a usual problem is mistaking a hypothesis for a known truth.

Special-Student-7-Rebutter
A frequently seen situation is a futile quarrel in which one side insists a thing and the other side insists another thing, but in fact, the 2 things are just hypotheses.

Special-Student-7-Hypothesizer
A problem with many Earthians is that they cannot distinguish between the strength of feel and the truthfulness of feel; they are like "This strongly feels to be true, so, this must be true!", a logical nonsense.

Special-Student-7-Rebutter
"cogito, ergo sum" seems an example: it is not any logical deduction; after all, it seems to be about how strongly he felt "I am".

Special-Student-7-Hypothesizer
However strongly he felt something, it is his personal issue: I or the truth do not care how he felt.


6: However Little Are Known for Sure, Any Theory That Includes Any Contradiction Is Absolutely Wrong


Special-Student-7-Hypothesizer
There are some persons who claim the right to insist absurd things, saying "As you do not know much, you cannot deny what I say!", but that is a totally false claim.

I can safely deny "1 + 1 = 3" even if I do not know much about higher mathematics.

Special-Student-7-Rebutter
Yes. That is because "1 + 1 = 3" is a contradiction.

Special-Student-7-Hypothesizer
However little is known, if a theory includes a contradiction, the theory is known to be wrong for absolutely sure.

I mean, as the theory includes at least some untrue hypotheses, you need to go and come back with a modified theory.

Although I happily admit that there can be multiple plausible theories at a time, I do not admit any theory that includes any contradiction.

Special-Student-7-Rebutter
The problem is that the person who persists to the wrong theory insists the consistency by shutting out inconvenient reasoning; that way, any absurd theory is consistent for him or her.

Special-Student-7-Hypothesizer
Yes. If he or she went in a certain direction in reasoning based on the wrong theory, he or she would certainly bump into a contradiction, but he or she adamantly refuses to go in that direction; if you suggest that direction, he or she flies into rage, abuses you, and runs amuck.


References


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2021-11-14

5: Being Legitimately Accurate and Objectivity-Blindness

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An indispensable qualification is to distinguish between what really is and what is (or can be) known. But objectivity-blindness seems pervasive.

Topics


About: truth

The table of contents of this article


Starting Context



Target Context


  • The reader will understand what being legitimately accurate is.

Orientation


There are some articles on truthfulness (here, etc.).

There is an article on the reality, observations, and interpretations of them.


Main Body

Stage Direction
Here is Special-Student-7 in a room in an old rather isolated house surrounded by some mountains in Japan.


1: What Is Required Is to Be Legitimately Accurate, Which Is . . .


Special-Student-7-Hypothesizer
Being truthful is the most fundamental, absolutely indispensable thing to be for any being.

Special-Student-7-Rebutter
Well, the problem is that some persons do not agree on that point.

Special-Student-7-Hypothesizer
I know, and it is rather 'many' or even 'most' than "some", among Biasians.

And I cannot help but admit that I have no means to argue with them, because I have no base on which I can build my arguments: I have to say like "This is true, is it not? Then, this should be also true. . . ", but being true or not does not matter to them in the first place . . .

Special-Student-7-Rebutter
Persuasions are usually done based on emotions, not based on truths, among Earthians.

Special-Student-7-Hypothesizer
But what I have to do persuasion on is that you should not be persuaded based on emotions.

Special-Student-7-Rebutter
You will have to do it based on emotions.

Special-Student-7-Hypothesizer
But I am claiming that you should not do a surreptitious thing as trying to persuade someone by manipulating his or her emotions.

Special-Student-7-Rebutter
A catch-22, huh?

It is fundamentally futile to be concerned with those "some", "many", or "most" persons.

Special-Student-7-Hypothesizer
Then, let us suppose that we are talking in a limited group of persons who agree on my premise.

To be truthful is to be accurate.

Special-Student-7-Rebutter
Of course.

Special-Student-7-Hypothesizer
But what is required for non-omniscient beings like us is to be legitimately accurate.

Special-Student-7-Rebutter
Is there such thing as being illegitimately accurate?

Special-Student-7-Hypothesizer
Yes, there is.

For example, you cast a die in an opaque box and declare "It's 6!", and let us suppose that that happens to be true, and you say "Look! I was accurate!".

Well, certainly you were accurate, but not legitimately accurate.

Special-Student-7-Rebutter
Are you condemning every kind of betting?

Special-Student-7-Hypothesizer
No. Betting is not declaring that you are accurate; betting is risking your money while you know that you may not be accurate.

Being legitimately accurate is stating what you really know.

As for the example of the die, being legitimately accurate is stating "The probability of its being 6 is 1/6.".

Special-Student-7-Rebutter
You should say like "almost 1/6", because no actual die is completely symmetrical.

Special-Student-7-Hypothesizer
"The probability of its being 6 is almost 1/6.", to be more accurate.


2: There Is No Such Thing As Prescience


Special-Student-7-Hypothesizer
I find it very foolish among Biasians that someone asserts something groundlessly and happens to be right and boasts his or her having been right: it is no credit to him or her; it was just a luck.

Special-Student-7-Rebutter
He or she is boasting that he or she had prescience.

Special-Student-7-Hypothesizer
But there is no such thing as prescience actually.

Special-Student-7-Rebutter
It is an inveterate myth among Earthians that there is.

Special-Student-7-Hypothesizer
And it is a very harmful myth.

A plain fact is that nothing can be known groundlessly; if a groundless assertion happens to be right, it is a luck, not prescience.

As Biasians believe in the existence of prescience, some zany disputes happen: one side asserts one thing and the other side asserts another, both groundlessly. For me, whichever side happens to be luckily right, the both sides are just unreasonable persons who make groundless assertions; I do not value one side any highly just because the side was lucky.

I say that it is very harmful, because it is the cause of such futile disputes.


3: Hypothesizing Is OK and Necessary, But Beware


Special-Student-7-Rebutter
But there is something called "educated guess".

Special-Student-7-Hypothesizer
There is: groundless-ness is not a matter of on or off; it is a matter of degree. So, a hypothesis is 95% likely to be right, while another hypothesis is 1% likely to be right.

I am saying that groundlessly ASSERTING is bad; hypothesizing is good.

If the 2 sides are hypothesizing, it does not become such an ugly dispute, but a fruitful argument: "Do you hypothesize so? Well, it is a possibility, although I do not adopt it. Maybe I can learn something from it although I do not totally adopt it.".

Special-Student-7-Rebutter
You can accept a hypothesis even if you do not adopt it.

Special-Student-7-Hypothesizer
Yes, but be aware that not every hypothesis is acceptable.

The absolute requirement for any hypothesis to be acceptable is to be consistent, internally and externally.

Special-Student-7-Rebutter
When you say "internally and externally" . . .

Special-Student-7-Hypothesizer
Being consistent internally means that the hypothesis does not contain any logical contradiction.

Being consistent externally means that the hypothesis does not contradict any known fact.

Special-Student-7-Rebutter
As new facts are known daily . . .

Special-Student-7-Hypothesizer
Any hypothesis can be consistent externally only so far; a new fact may deny the hypothesis, and then the hypothesis will have to be modified or retracted, which is the standard process of improving one's worldview.

There are some persons who claim the right to insist on their inconsistent hypotheses, but I do not admit such a right: any inconsistent hypothesis is definitely wrong and they have to come back with modified or new hypotheses.


4: A General Checkup on Objectivity-Blindness May Be Due


Special-Student-7-Hypothesizer
I find some people among Biasians who cannot distinguish between what really is and what is (or can be) known.

They insist that something does not exist just because it is not or cannot be known, a totally stupid idea.

Special-Student-7-Rebutter
They "cannot" or 'will not'?

Special-Student-7-Hypothesizer
I was suspecting that they 'will not', but now I have begun to suspect that it is a kind of congenital condition, like color-blindness. I would call the condition 'objectivity-blindness'.

Special-Student-7-Rebutter
Are there many who are suffering "objectivity-blindness"?

Special-Student-7-Hypothesizer
I see many and very perturbingly, even among highly-educated people.

For example, there is a mathematics professor who is claiming that a function is not legitimate just because humans do not know its behavior and the nature of the function would change if the understanding by humans on its behavior was changed; he is claiming also that the natural numbers set does not exist just because humans do not know well about most of its elements, and also that the square root of 2 does not exist because humans do not know its whole digits.

Special-Student-7-Rebutter
. . . Is this about him, personally?

Special-Student-7-Hypothesizer
No. It is rather a pervasive phenomenon.

That odd interpretation of the quantum mechanics seems to keep being mainstream.

Special-Student-7-Rebutter
What is "That odd interpretation"?

Special-Student-7-Hypothesizer
It insists that wave functions are objective entities, which leads to that foolish Shrodinger's cat.

Special-Student-7-Rebutter
And your interpretation is . . .

Special-Student-7-Hypothesizer
The quantum mechanics has already abandoned describing what the objective reality is (because of the uncertainty principle) and is about what humans can predict. So, naturally, wave functions are not about how particles really are, but are just about what humans can predict, as well as the uncertainty of the life or death of the cat is not about that the cat is in a half-alive-half-dead state, but is just about that humans cannot predict the state.

Special-Student-7-Rebutter
That seems a quite natural interpretation.

Special-Student-7-Hypothesizer
But there are some people who persist to that odd interpretation . . .

Special-Student-7-Rebutter
I wonder why.

Special-Student-7-Hypothesizer
I can only guess that they cannot distinguish between what really is and what can be known.

Special-Student-7-Rebutter
And is it a congenital condition? Incurable?

Special-Student-7-Hypothesizer
Maybe.

Special-Student-7-Rebutter
you cannot blame color-blind people "Why can't you distinguish colors?!", as well as you cannot blame objectivity-blind people.

Special-Student-7-Hypothesizer
But they should be at least aware that they are objectivity-blind. Maybe, a general objectivity-blindness checkup is due.

Special-Student-7-Rebutter
What kind of checkup will be that?

Special-Student-7-Hypothesizer
It will consist of very simple questions, like "Suppose that there is a particle that does not interact with anything at all, so, it cannot be detected. Do you conclude that the particle does not exist?"

Special-Student-7-Rebutter
The question has already declared "there is a particle", which means that the particle exists . . .

Special-Student-7-Hypothesizer
Nevertheless, objectivity-blind people will answer that it does not exist.

Special-Student-7-Rebutter
Will they?

Special-Student-7-Hypothesizer
Another question may be "The diagonal length of any unit square cannot be digitized in any finite sequence of digits. So, do you conclude that the length does not exist?".

Special-Student-7-Rebutter
It is about the finite-digitizability of the length, not about the existence of the length . . .

Special-Student-7-Hypothesizer
But there are some people who claim the nonexistence, as a matter of fact.


References


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