So let me see if I understand you. You are saying that we know whether or not something was produced by design, by knowing whether or not it was produced by a "person". But what it takes to be a "person" is left undefined, and extremely vague. Doesn't that leave whether or not a thing was created by design as undeterminable?

You wrote: "So you could say that ... both of them are possible, but it is incorrect to say that they are "both possible" Why is one correct and the other incorrect? I think the two say the same thing. — god must be atheist

English is probably not your first language, because you seem to be missing out in some nuances. The way I use "both possible" implies the two together, collectively. So to say it more clearly, it is impossible to have both. This uses "both" to refer to the two collectively, and we agree that they are mutually exclusive, so it is impossible to have both, together. But when I said they are "both possible" it refers to each of the two individually, and individually each is possible. Therefore I can say that both are possible, but to have both is impossible. "Both" is used in two distinct ways, one time referring to each of the two individually, and the other referring to the two together, collectively. Sorry no confusion or equivocation was intended.

Again, congratulations for catching me on this mistake. Please reconsider my stance as corrected in this post. Thanks. — god must be atheist

OK, but as I explained in my last post, directed at alcontali, I believe that it is impossible for order to come from disorder, in any absolute sense (meaning order cannot come from absolute disorder).

I don't think that Aristotle was particularly familiar with self-organizing systems or the concept of spontaneous order: — alcontali

"Spontaneous order", is nothing but a rehash of the old concept "spontaneous generation", which was long ago disproven. It's pie in the sky.

You seem to be unfamiliar with the concepts of "spontaneous order" and "emergent behaviour" which are quite modern, only a few decades old, actually. — alcontali

As I said, your example of game theory starts with the existence of things, which itself implies order. So the theories you refer to do not describe order coming from disorder, only one form of order coming from another form of order. If you believe that these theories describe order coming from disorder, you have been misled.

Unlike metaphysics, mathematics has made incredible progress in the 20th century. — alcontali

Yes, I've noticed that mathematics has made incredible progress in misleading people. Luckily I'm not one of them. You ought to learn how to read these theories more critically and free yourself from the binds of such deception.

Yes one can certainly use the above rule in applications like in adding an apple to another to get two apples, but the properties of Apple like it having a seed for example, a DNA, etc.. all those are particulars that are not inferred from 1+1=2, so we need to abstract away those properties. Moreover if we speak in the strict formal sense then 1+1=2 can stand by itself as a syntactical game prior to any application, and so the abstract model of it would indeed provide nearer semantics to the formal essence of 1+1=2. — Zuhair

OK, now the question here is why does "2" represent one object, and not two objects. Intuitively I would say that the first "1" in "1+1=2" represents an object, and the other "1" represents an object, and "2" represents two objects. By what principle do mathematicians assume that "2" represents a single object, which might be called the number two?

Platonism is the easiest way to go about mathematics. — Zuhair

Perhaps Platonism is the "easiest way", but it is really nothing more than a cheat. Instead of recognizing, and understanding that a phrase like "1+1=2" is completely useless, and therefore meaningless, unless it is applied towards some real objects, in a real situation, the mathematician wants to say that it is implied within the phrase itself, that real objects are referred to. But this is contrary to the nature of language itself. In no instance of language use, is it inherent within the particular instance of usage, that there is necessarily objects being referred to. That this is the case, that no word necessarily refers to an object, is what allows for the existence of deception. So, claiming, or asserting that there is necessarily objects referred to, with a phrase like "1+1=2", is itself an act of deception, because there is really no language which can necessitate that if the word is spoken there is necessarily a corresponding object.

Now, the key to understanding, I believe, is to recognize that using "2" is an act which makes two objects into one object. We refer to the pair as if they are one object, using the numeral "2", but we have to remember that what is really referred to is two distinct objects, which are only made into one object through this artificial process, this synthesis, which is accomplished by someone uniting them, putting them together as one object, simply by calling them "2". So if we assert that "2" stands for one object, the true essence of this object which it stands for, is that it is really two objects which is only one object because we say that it is, and we have made it thus (one object), simply by saying that it is.

From the philosophical point of view this applicative reduction might look more prudent, but from the pure mathematical point of view, definitely platonic models would be preferable, since they are more direct engagements of what those mathematical statements are saying. — Zuhair

This is what I dispute though. The platonic model does not really engage with what the mathematical statements are truly saying. It is simply a cheat, an easier way for the mathematician, a way to avoid analyzing and understanding what the statements are really saying. Look, "2" really says two objects, and the mathematician just says consider those two objects as one object. It doesn't matter to the mathematician that there are no real principles whereby the two are considered as one, we'll just take it for granted that the two are one, and this will allow me to make all sorts of neat axioms. So the mathematician might assert that "2" says one object, and this is "what those mathematical statements are saying" but in reality we all know that the meaning of "2" is two distinct objects. So what the mathematical statement is really saying is that there are two objects here. But what the mathematician is saying is just bear with me, and consider that these two are one, so that I can perform my magic.

Not by a human being. What I wrote is "I'm using the sense of 'natural' where it's distinct from 'made by a person.'" I chose those words carefully. "Person" is broader than "human." There can be persons of different species, or even "supernatural" types of persons, if there were to be such things. — Terrapin Station

OK, what defines "a person"? Is a beaver a person, or a bird a person? Is a rock a person?

We learn that we're wrong, when we are, via an investigation into the object in question. Again, we're not simply in the dark when it comes to scientific, forensic, etc. investigations. We can formulate hypotheses and then discover that our assumptions were wrong. The butler didn't kill Mr. Jones, the cook did, for example. We can discover such things via systematic investigations. — Terrapin Station

Now I understand why we might find ourselves to be wrong. We might assume that a beaver is not a person, or that a rock is not a person, and then find out at a later date that these things really acted as persons. Aren't you really just appealing to a division in the classes of "agency"? There is a type of agent which acts with intention (person) and a type of agent which acts from a simple chemical process (like a cleaning agent).

Suppose x is defined as not spatial, "outside of space". Well, then obviously x is nowhere to be found. And x cannot have any extent, volume, area, length, or the likes, not even zero-dimensional (like a mathematical singularity). — jorndoe

This is somewhat incorrect, "outside of space" can be found with the appropriate conceptions. The problem here is that "mathematical singularity" is really a faulty (self-contradictory) concept. And if mathematicians would recognize this, and remove such conceptions from their lexicon we could represent true zero-dimensional existence as outside of space. The glaring problem is that mathematicians have occupied the category of non-spatial existence with their "mathematical objects" (Platonic realism), thereby leaving it impossible to let any other type of existence into this category.

Mathematicians treat numbers and other mathematical concepts as real objects, which of course have no spatial existence. This creates an artificial division between the spatial world (physical world which numbers are applied toward understanding) and the non-spatial world (the world of mathematical objects, the existence of which the mathematicians have assumed to support their axioms, and have incorporated into those axioms). This division does not properly represent the real categories of spatial and non-spatial existence, found in the real world, and thereby restricts our capacity to understand the real world.

Spacetime is an aspect of the universe, and "before time" is incoherent. — jorndoe

Suppose x is defined as atemporal, "outside of time". Well, then there can be no time at which x exists. And there can be no duration involved, x cannot change, or be subject to causation, cannot interact, and would be inert and lifeless. — jorndoe

"Outside of time", as well as "before time" can easily be understood when one considers the true nature of time. Time passes at the present. It is this process, of passing at the present, which gives reality to time. So to be within time means to have been present, and this is past. Therefore anything in the future is "before time", or "outside of time".

They are mutually exclusive, yes. But they are both possible.

Much like it is possible that god exists, and possible that god does not exist. One excludes the other, but both are possible.

You have to see that. If you don't see that, then you can't see how your criticism isn't right. — god must be atheist

There is nothing wrong with the criticism, because the one (if it is correct) excludes the possibility of the other. So you could say that each of them, or both of them are possible, but it is incorrect to say that they are "both possible", as this implies the two of them collectively.

And you state at #8 "it does not exclude the chain of events...", when actually 1 - 5 does exclude that chain of events. By saying this you imply that the two possibilities are not mutually exclusive, when actually each one excludes the possibility of the other.

The fact that order appears out of chaos, however, does not strike me as particularly special, or even as being such hint. — alcontali

It is actually impossible for order to appear out of pure chaos, this was demonstrated logically by Aristotle. To state the opposite is to misunderstand, or change what is meant by "pure chaos".

Say that a thing maximizes its own integrity. If it can enter a situation in which other things contribute to its own integrity, it may favour to stay in that situation. If these other things can also maximize their own integrity by maintaining that situation, then none of the things involved, is willing to change the situation. Such situation may be highly improbable, but once it exists, it will refuse to disappear. So, that creates a new, stable thing consisting of a game-theoretical equilibrium between sub-things. — alcontali

The problem with this analogy is that you already assume the existence of "a thing", and this implies order. "A thing" is an ordered existence. Lack of order would actually mean a lack of things. In Aristotelian terms a lack of order would simply be the "potential" for existence of a thing. So if you are describing how order comes out of non-order, you cannot start with the existence of a thing, because this is to presume the existence of order already.

So, incredibly complex and orderly situations tend to arise pretty much spontaneously from chaos. As far as I am concerned, they do not necessarily point to an underlying design. They could just arbitrarily be satisfying the conditions of particular game equilibria. — alcontali

Maybe you do believe this, but you seem to misunderstand what "chaos", or complete lack of order really entails.

As tim points out, #1 is the correct form. But this simple argument is rather pointless without including the difficult part, which is to demonstrate how a god is necessary for the existence of order.

When we get info that we're wrong, then we make the adjustment that we need to make. — Terrapin Station

How could you ever get info that you're wrong though? If, being created by design required , by definition, that the thing be created by a human being, and this principle is really wrong because something else like another form of creature or something, actually creates by design as well, how could you ever get information that you're wrong? It's impossible that something other than a human being could create through design, by your very definition, so it's impossible that you could ever get information that something which was created in some way other than by a human being, was actually created by design.

You're left with judging whether the thing was created by a human being in order to determine whether the thing was created by design. And accepting this false principle, that human beings are the only possible type of being capable of creating by design, closes you mind to the reality that other things like beehives, birds nests, and beaver dams are created by design as well.

Here's the proof:

1. Order can only be achieved by an orderer.

2. Only intelligent planners can be orderers.

3. Planners and orderers have order inside of themselves. They are ordered.

4. Nobody can order himself from scratch.

5. Therefore orderers must be ordered by a previous orderer.

6. This leads to infinite regress of orderers.

7. This is possible.

8. But it does not exclude the chain of events, that an orderer can be created by chance in a chaotic system. — god must be atheist

To introduce #8, you must reject the conclusion stated as #5. These two contradict each other. But #5 is produced as a conclusion from #1, #3, and #4. So, the order which an orderer has, can only have been produced by a previous orderer, And #8, that an orderer could be produced by chance is excluded by these premises.

We can make a distinction between things that people make and things that aren't made by people. — Terrapin Station

The point though, is that there is a number of problems with your approach. The first problem is that if it requires that we see a person making the thing, or that particular type of thing, in order to say that the thing is artificial, then when we find something which has already been made, and we haven't seen a person making that type of thing, we have no way to make any judgement as to whether or not it's artificial.

So TheMadFool has a different approach, claiming that there are certain characteristics which demonstrate that an object has been 'made', or designed, and we can make a judgement based on that criteria. This approach is much more useful, and widely applicable than yours, allowing us to judge a thing by its properties, rather than requiring that we observe the creation of the thing. In many cases, (such as with ancient artifacts) observing the creation of the thing is not possible.

The second problem is even more substantial. This is the fact that you are making an arbitrary division between what is "designed", and what is not designed, based on the assumption that only human beings are capable of designing things. And again, archeological evidence poses a problem here because the humanoid beings, which are not properly "human beings" were designing things. Furthermore, when we see things like a beehive, a bird's nest, and a beaver dam, applying your principles we would have to say that these things are not "designed", because they are not built by human beings. But in reality, "design" is determined by intention, and these things are just as much intentional as anything produced by human beings. All you have done is created an arbitrary division between human beings and the rest of the natural world, one which is not at all supported by the science of biology. Biology gives no such special status to the human species.

I just thought of something and would like your opinion on it.

Consider the universe as the universal set U. Now the design argument works by picking a subset D consisting of human-designed objects and then generalizes it to the set U.

Now, someone may reject the design argument by referring to another subset of U, call it R, which consists of objects that have order e.g. a flower but obviously isn't human-designed.

As you can see both arguments are on an equal footing, referencing a subset of U and then generalizing to U itself. — TheMadFool

What I see as the issue, is how we define what constitutes a "designed" object. Terrapin's approach is to limit "designed" to things made by human beings. But as you can see there are numerous problems with this approach. It is not a useful, or helpful approach, and may lead to misunderstanding in numerous different ways. The more realistic approach is to determine the characteristics of "design", and judge things accordingly. I propose that "intention" is what defines design, such that anytime there is evidence of intention, design is implied, regardless of whether the thing was produced by human beings.

Thanks for the reference Zuhair, but I really can't read the symbols used. It's like learning a new language for me, and it's a type of language which is even more difficult than a normal language, which I can't learn a new one anyway because that itself is very difficult for me. I have enough trouble with English.

Having said that, I see that the paper takes the premise of Platonic realism, assuming that symbols like "2" represent a thing called a number. This is the premise which I've been explaining to fishfry is incorrect. I believe that to adequately understand the use of mathematics it is necessary to apprehend that each time these symbols are used, in different circumstances, they represent different things, dependent on the circumstances of the application. What the symbol represents is not "a number", but a specific and unique object determined by the application of the mathematics.

So for example, when we count something, there is necessarily something which is being counted. One might just count, and claim to be counting "the numbers", having no tangible objects being counted, but as I explained, this is not a valid count. If nothing is being counted except "the numbers", then the start and finish are arbitrarily chosen, and the conclusion of "how many", which is what is determined by a count, is also arbitrary. Therefore any such count (how many), cannot be properly justified, it is just a function determined by the rules of the count, which are arbitrarily chosen. This is just an exercise, a practise, to demonstrate an understanding of the rules, like practising logic (as we discussed), where the symbols do not represent anything. If one were really going to count "the numbers", the count would never be finished. Therefore a count of "the numbers" can never be a valid count.

In reality then, the symbols in such a practise do not represent anything. Logicians recognize this when they practise the laws of logic using symbols which do not stand for anything. They know that using such symbols is just an exercise to help them learn the laws of the system. But for some reason, mathematicians like to say that such symbols actually stand for objects (Platonic), things that they call numbers, and such. But we all know that such objects are just imaginary, and have no real existence whatsoever. So we ought to recognize that these mathematicians are just fooling themselves, claiming the real existence of non-existent imaginary objects, immersing themselves into this fantasy world which the paper calls "model theory".

It's the natural/artificial distinction — Terrapin Station

As I said, there is no scientific validity to such a distinction. Human beings are natural and so are the things created by human beings. The "artificial" is just a specific type of natural thing.

No one makes a universe. It's a natural occurrence. — Terrapin Station

Yeah, just like a watch is a natural occurrence. You know, the principles employed by modern scientists tend to break down the division between artificial and natural. Human beings are considered to be a "natural occurrence", so all things which human beings create are also natural occurrences. So it's really meaningless to say that the universe is "a natural occurrence", because this doesn't distinguish it from anything else; all things are natural occurrences, even watches.

You'd need knowledge that universes are the sorts of things that are usually made by universe-makers. — Terrapin Station

Who else would make a universe?

ps -- I should add this so you understand why you are wrong. It's a basic principle of math that the same symbol means exactly the same thing each time it's used in an argument or equation. For example when we say that for all even natural numbers n, 2 divides n, then even though n ranges over all possible even numbers, in each particular instance n means the same thing each of the two times it's used.

Likewise when we say 4 + 4 = 8, it's basic to all rational enterprise that the symbol '4' refers to the exact same thing each time it's used. Without that, there could be no rational communication at all. Natural language is symbolic. If I say that today it's raining and today it's Thursday, and you claim I can't assume that "today" refers to the same day each time I use it, then we'd all still be in caves. You couldn't say "pass the salt" without someone saying, "What do you mean pass, what do you mean salt, what do you mean "the"? You are denying the foundation of all symbolic systems from natural language to computer programming to math. — fishfry

Try looking at it this way fishfry. There is a difference between what a symbol "means" (as said in your fist paragraph above), and what a symbol "refers to", (as said in your second paragraph above). So we can say that a symbol must always have "the same meaning" in order that it be useful, but the symbol doesn't necessarily refer to the same thing each time it's used. I use the word "house", for instance, and we say that it has the same meaning each time I use it, but I use it to refer to many different things which are all houses, so it doesn't always refer to the same thing.

What is important to understand here is that the phrase "the same meaning" does not use "same" in a way which is consistent with the law of identity. "Meaning" is the type of thing which varies according to circumstances, matters of context and interpretation. So in reality, even though we think "that the same symbol means exactly the same thing each time it's used", and this is necessary for a symbolic system to work, the very opposite of this is what is actually true. There must be nuanced differences in the meaning of "house", each time that I use it to refer to a different house, or else people would always think that I am referring to the exact same house each time I use the word. So "same" here really means "similar", and this is a qualitative identity, which is not what is described by the law of identity.

Qualitative identity is used to say that two things are equal, or "the same" according to some principle, or inferred criteria of judgement, but it does not mean that they are "the same" in the sense dictated by the law of identity, which would require that they are not two distinct things, but one and the same thing.

The way that we reach an abductive conclusion of there being a watchmaker from a watch is simply via knowledge that watches are artifacts that are intentionally made by people. We know (there are) watchmakers, we can observe them work, etc. If we didn't have such knowledge, the notion of a watchmaker wouldn't be justified. — Terrapin Station

That's actually a straight inductive conclusion. We see that watches are made by watch-makers, and conclude that all watches are made by watch-makers. So when we find something which looks like a watch, and acts like a watch, and we say that it is a watch, then we apply the inductive conclusion as a deductive premise, to make the further conclusion that the watch we have found was made by a watch-maker.

But other people believe that they are correct. What are you going to do, shout at each other until one gives up? — Isaac

No, reasonable people discuss things. Sometimes it takes a long time, many years of discussion, but there's no rush, and no need to shout, that's impatience.

You talk about ensuring things are in line with our experience, yet you maintain this bizarre notion that what is 'correct' can be ascertained by thought alone in complete contradiction to our overwhelming failure to do so. — Isaac

Actually, success in "doing so" requires motivation, the desire to determine what is "correct". And we can only proceed towards determining what is correct if we have a good understanding of the difference between right and wrong, and this is obviously based in an understanding of morality. Morality is the knowledge which deals with the difference between good and bad, right and wrong.

People still disagree now about exactly the same matters they disagreed about thousands of years ago. If a thousand years of discussion hasn't yielded a sufficiently convincing answer, where does that leave your 'belief' when measured by your own standards of correspondence with experience? — Isaac

This is because we've had a regression, the resurgence of monism. The philosophical problems discussed by the ancient Greeks were mostly resolved through the application of dualism. This lead to many centuries of advancement. It is false to say that the knowledge of today hasn't advanced from the knowledge of thousands of years ago. But with that advancement has come a turning away from the very principles which allowed for the advancement, and a return to the monist arguments of those ancient societies.

But perhaps you could give me a reference that supports your view. — fishfry

It's not a matter of giving you a reference, it's just a matter of whether you understand the reason or not. Do you know how to count? Say you have "1", and that 1 signifies something. And, you have another "1", and that 1 signifies something. In order that these two 1s, when they are put together (1+1), can add up to two, they must each signify something distinct from the other. If each of the two 1s signified the very same thing, there would not be two things, only one. Do you understand the reasoning here?

When we count objects, each object is counted as one (1), and so each object is represented by the symbol "1". So we count them, 1 plus another 1 makes 2, plus another 1 makes 3, plus another 1 makes 4, etc.. Each "1", must necessarily represent a distinct and separate object from every other "1", or else we would not have the multiplicity implied by the count, "2" "3" "4", etc.. It's not the case that the fourth object counted, when we point to it and count it as "4", is represented as 4, each distinct object is represented as 1. And, that each 1 represents a distinct object is absolutely necessary, or else the count would be invalid.

ps -- I should add this so you understand why you are wrong. It's a basic principle of math that the same symbol means exactly the same thing each time it's used in an argument or equation. — fishfry

You are clearly wrong, and have given this absolutely no thought, or else you would see how wrong you are. When I say I have 2 chairs at the table, and I need another 2 chairs at the table to have 4, so that I can accommodate my guests, it is very obvious that each instance of "2" must represent a distinct pair of chairs. If the two 2s represented the same pair, I could not get four chairs out of them. I would be stuck with only one pair of chairs.

Likewise when we say 4 + 4 = 8, it's basic to all rational enterprise that the symbol '4' refers to the exact same thing each time it's used. — fishfry

Again, you are very obviously wrong here, and you have clearly given this no thought or else you would see immediately how wrong you are. In the equation "4+4=8", each "4" must represent a distinct group of four things, or else they could not produce the sum of eight things. If both the 4s represented the same group of four things, there is no way to get a group of eight things, which is what is signified by "8".

If you deny that the number 4 is the same as the number 4 you are entitled to your opinion, but that kind of sophistry is of no interest to me. — fishfry

I just explained this. When the symbol "4" is used twice in "4+4=8", it must signify a different thing in each of the two instances, or else 4+4 would not equal 8. If the two 4's both signified the same group of four, there would not be eight, by putting together the two things represented by the two 4's, there would only be the same four. Therefore the two 4's in 4+4 must signify different things or else 4+4 could not equal 8.

If you have anything of relevance to say, address my post, show me how it is possible that when you count, and you add 1+1+1+1 etc., each instance of "1" signifies the same thing. If you cannot address this issue you are just blowing smoke, saying that "1", or "2", or "4", always represents the same thing.

But in the end you have now said, and not for the first time, that you don't believe the number 4 is the same as the number 4. There is no conversation to be had (at least on this topic) with someone who professes such an obvious falsehood. — fishfry

To be clear, I do not believe there is any such thing as the number four. Aristotle decisively disproved this Pythagorean idealism (currently known as Platonic realism) many centuries ago. What is the case, is that we use this symbol, written as "4", and each time it is used it signifies something, usually something different from the last time. When it is used, it may or may not signify the very same thing as in another instance of use, but in the vast majority of instances it signifies something different each time. Therefore the symbol, or numeral "4", does not represent the number four. This is a false assumption.

ps -- Wiki agrees with me. — fishfry

I was expecting this sort of reply, and I've already addressed it:

And if you insist that this is "the conventional" interpretation, that is not a justification. All this means is that "the conventional" interpretation is wrong, as I've demonstrated. — Metaphysician Undercover

The number 2 is identical to the number 2. — fishfry

I went through this with Zuhair already. It is impossible that the numeral, the symbol "2" represents the same object every time it occurs. If it did, then both the 2's in "2+2" would refer to the same thing, and 2+2 would not equal four because there would just be the same two.

This is fundamental to the nature of counting. Each thing referred to by "1" must be a different thing, or else there would not be a multiplicity. "1+1" must represent two distinct things, or else it would not equal to two things. And "1+1+1" must represent three distinct things or else there would not be three. And so on, and so forth, each occurrence of the same numeral "1", must represent a different thing when we count, or else there is no multiplicity, only the same thing over and over and over again; and the sum of the count would be invalid because there would only be one thing being counted,.over and over again.

But in ZFC, the domain of discourse in which you originally claimed that identity differs from equality, I tell you that you are incorrect. But I have said nothing new, I've written the same things over and over. — fishfry

That's what I've been saying, you keep asserting the same thing over and over and over again, without justifying your claim. I've demonstrated how equality is different from identity. So unless you can demonstrate how it is that equality is identity, in set theory, all you are doing is demonstrating that you misinterpret.

How can you possibly judge the 'rightness' or 'wrongness' of the direction of speculation? The idea doesn't even make sense. Speculation is just that, meaning we don't know if it's right or wrong before we test it. — Isaac

I disagree, metaphysics can guide us in the right direction through the use of logic. So for example things which are impossible and don't need to be tested, because we can know that they are impossible without testing them, ought to be excluded from speculation. But I'm not saying that string theory is speculation into impossibilities, because I don't know enough about it to make that judgement. This is just an example of how it is possible to know that speculation is in the wrong direction.

Furthermore, all speculation proceeds from principles, fundamental judgements, and I believe that some judgements at the base of modern speculative physics are incorrect. Principally, they employ a notion of time which is inconsistent with what we experience. That's what's wrong about it.

I meant why the distinction between static space and active space, since the shape of an object is not necessarily static. — leo

Well I went through this already. An object must really be a static thing, because if it changes it is no longer the same object. Sure we say that it is the same object, only changed, but logically if it has changed, it can no longer be the very same thing. Aristotle tried to deal with this problem by employing the concept of matter, which allowed that the object would remain the same object, despite changing its form, so long as its matter stayed the same.

So Aristotle distinguished change of shape or form, from locomotion, as two distinct types of activity. In modern times, we have come to understand change of shape as the locomotion of a thing's parts. So we no longer have these two distinct types of activity, all is understood under the terms of locomotion. Change of the shape of an object, is supposed to be the movement of parts relative to each other. But then the parts are themselves objects, moving relative to each other, and there is no justification for the claim that a multitude of objects is really one object, the original "object". Either the circumstances being observed is a multitude of objects, or it is one object, but it can't be both at the same time because this is contradictory.

That is the problem with the part/whole ontology. Saying that an entity, an object which exists as a single, individual unity, is composed of other objects which are parts, is really contradictory. This is because we then consider the same thing to be both one object, and a multiplicity of objects, at the same time, and this is contradictory, like saying 1 is at the same time, 2. If we divide the one unity into parts, then it is no longer one unity. It cannot be divided and whole at the same time. So the one object, as a unity is divisible into parts, but it cannot actually be composed of parts, if the parts are considered to be objects themselves.

If the object, as a unity is not composed of parts, then it cannot be changing. If it is composed of parts, and changing, then the parts cannot be considered to be objects, and their activities cannot be understood as objects moving relative to each other.

No I'm not saying that, I said that the definitions refer to it like a thing, some sort of container in which objects move. In physics space used to be thought as a medium (the luminiferous aether), then failures to detect it experimentally led to abandon the idea of it as a medium (as Einstein did with special relativity in which there is no more reference to an absolute space but instead to relative reference frames), and then Einstein reintroduced it as some sort of a medium in general relativity since in it space has properties such as curvature. But even though in his theory space has properties, Einstein was well aware that space is a "tool of thought" (that's his own words), in no way did he pretend that his theory somehow proved that space is an actual medium that really does curve, only people who misinterpret him and misinterpret the function of scientific theories say that. — leo

I accept this description, but it does not explain how objects exist within space, yet space is just a tool of thought. The inconsistency, or contradiction, remains. If the conceptions of "space" model space as a medium within which objects exist, then it is absolutely incorrect to say that space is a "tool of thought". Space is something which is modelled as a medium within which objects exist. It is not modeled as a tool of thought, so it is incorrect to say that space is a tool of thought, because it is represented by the models as a medium within which objects exist. If we model water as something we can swim in, then it is incorrect to say that water is a tool of thought, that is not how it is modelled.

It could be that there really is a medium that permeates everything, or it could be that there is pure void between things, both ideas are compatible with what we observe. If there is pure void between things then space isn't a medium, it isn't an actual thing. — leo

It doesn't matter if you call this medium "pure void", it's still a medium. So your claim of two possibilities, medium, and pure void, is inaccurate because "pure void" is really just a special type of medium, and so there is really only one choice, medium. Many people speak of "pure void" as if it were something other than medium. But when we come to realize that "pure void" just refers to a special type of medium, an absolute medium which consists of absolutely nothing but itself, then we realize that it doesn't make sense even to speak of "pure void".

It does make sense if it is said conceptually and not literally. — leo

I don't understand this distinction. Do you recognize that a model must model something? If one were to make a model, and it didn't model anything, it would just be random nonsense, and not a model at a all.

So if you model planets as moving through space, it makes no sense to say that this is just what the model shows, and the planets are not really moving through space, we've just modelled them that way. If you model planets as moving through space, and insist that the planets aren't really moving through space, it's just that the model shows them as moving through space, then all you are doing is asserting that the model is wrong.

If simultaneously one person can imagine space as flat, some other person as curved, some other person as shrinking and expanding, some other person as being displaced by objects, do you not see that space is a concept, and that people conceptualize it by analogy with what they do observe? — leo

Not at all. What I would conclude from this is that space is a real thing, because many people are talking about it, but they just don't understand it, and this is evident because their concepts of it vary. It's very similar to when a few people try to recount an incident from many years ago. Some will remember it in one way, others in another way. This doesn't mean that the incident isn't a real thing which really happened, it just means that the people haven't conceptualized it well.

I don't know how it could be a plane, but I don't believe in fate and determinism, so I've never given it much thought.

Breaking down the sci-fi part, there's a plane of existence, (think of it as overcoming a mountain, though it instead of over it), that allows these two beings to meet, across the set of all possible worlds. — Wallows

"Across the set of all possible worlds" implies necessity. So that meeting was necessitated. This is sometimes called "fate", which determinists take for granted. To meet was their fate.

Speculative physicists are headed in the wrong direction.

I suppose Trump's pulling the troops from Syria was just the fulfilling of an election promise - one made to the Russians.

I don't know why you make a distinction there. In both cases measurements are involved, in both cases the measurements can change (the shape of an object can change, so can the distance between objects). — leo

Do you not see a difference between measuring an object, and measuring the distance between two objects? In the first case, you would be dealing with the properties of one individual object, and in the second case you would be dealing with a relation between two objects.

There are other conceptions of space. The one customarily used in physics is something like:

a boundless three-dimensional extent in which objects and events occur and have relative position and direction (Merriam-Webster dictionary)
the dimensions of height, depth, and width within which all things exist and move (Oxford dictionary)

Notice how these definitions do not refer specifically to measurements of objects or measurements between objects, they refer to a thing within which objects exist and move. — leo

If space is "a thing within which objects exist and move", how can it not be a substance? You are saying that it is a thing, like a medium, within which objects exist, like they exist in water, or air. How could there be a thing, with objects existing within it, and this thing does not have substantial existence?

For instance in classical physics, when two objects move towards each other they move in space, space doesn't shrink between them. Sure the distance between them decreases, the unoccupied volume between them shrinks, but the reference background relative to which objects are tracked, space, doesn't shrink. — leo

OK, so there is a thing, with objects moving within it, just like objects move in water or air, but this thing is called "space". How can the objects move within this "space" without changing this thing? If an object moved, wouldn't some of the space be displaced, and therefore itself be moved? If the objects moved closer to each other, than the amount of space between them would necessarily shrink, as some would have to move aside, or else it might compress.

Now of course that reference background is not something we observe or detect, it is a reference frame that is defined from things we do observe, which is why I say that this background is not something tangible, is not a material substance, it's a concept, a tool of thought, and to treat it as tangible like an object is the fallacy of reification. — leo

Now you are contradicting what you said above. You said that space is a thing within which objects exist. How could this thing (space) be just a concept, or tool of thought? Either there is a thing (space), within which objects exist, or space is just a concept, a tool of thought. But it doesn't make sense to say that the thing within which objects exist, and move around, is a concept. Which do you believe? Is space a medium which has objects within it, as you say is the customary definition in physics, or is space just a concept or tool of thought, as it is in you ontology?

This is the problem I told you about already. Our definitions, concepts and models, treat space as a real, substantial thing, a medium within which objects exist,. Also, you use and refer to those concepts in your argumentation. Yet you assert an ontological principle which contradicts this, that space is only conceptual. Do you not realize that the definitions you cite do not support, and are actually opposed to the principle you assert?

The definition I use would be something like a material with particular physical characteristics (Cambridge dictionary), whereas your definition seems to be something like the essential nature underlying phenomena (Oxford dictionary). So obviously if we're not using the same definition we talk past each other when we talk about substance. — leo

OK, since we have different ideas of what substance means, lets leave that word. Let's just focus on your definition of "space" as a thing within which objects exist, and we'll forget about whether this thing is properly called a substance or not. Clearly you must see that this thing is not merely conceptual. How could objects exist within it if it were only conceptual?

Now that you know in what sense I use the words "space" and "substance", and so as to not get too carried away, the whole point of the discussion is what does it mean to say that space curves? Plenty of people say that gravity is the curvature of space, that planets orbit the Sun because space is curved around the Sun and because they follow straight lines in curved space, people are made to believe that we have found the cause of gravity, that this cause is that space is curved, as if space was a tangible thing, a tangible material, a tangible substance that we have detected to curve, and as I keep saying this is false, we have detected no such thing, the curvature of space is an abstraction, a concept, a tool of thought, not something that is physically detected in any way, and to treat that abstraction as a material thing is the fallacy of reification. — leo

OK, now according to your definition, space is a thing, like a medium, within which objects exist and move. Would you agree that there is a property of this medium (space) which causes things to move in a curved trajectory when we would otherwise think that these things ought to travel in a straight line, and that this is why some people talk about a curved space? If it is not a property of this thing, called space, then what could it possibly be that causes this? It cannot be that the concept of space, or that the tool of thought causes this curved motion, because the concept is simply supposed to represent, model, or demonstrate an understanding of this curvature.

People are made to believe that we can't model gravity precisely without invoking a curved space, as a supposed proof that space really is a tangible material that really does curve even though we don't directly observe it, this is false, we can model observations as precisely without invoking a curved space. — leo

OK, let's suppose that this is true, space can be modeled with or without the curvature, and each model is as accurate, and reliable as the other. What does this indicate other than the fact that we really don't know what space is?

You CLAIM they have different meanings but have not even attempted to defend or explain your claim but only seem to be avoiding the question. — fishfry

This is ridiculous. I've explained numerous times in this thread how equality differs from identity. "Identity" applies to one thing, the same thing, its identity. So "identity" relates to what makes one specified thing other than everything else. "Equality" applies to two distinct things which are judged to be "the same" in a specific way. You might consider that "identity means "the same" in an absolute way, whereas "equal" means "the same" in a qualified, relative way. The example I gave is that two human beings are equal because they have the same rights, but they are not the same, because they each have a distinct identity.

Your task, as it has been since we first engaged in this thread, is to demonstrate that in mathematics "equality" is "identity".

I deny that mathematical equality differs from identity in set theory, except in a handful of casual conventions that can easily be rigorized on demand. — fishfry

That is the point you keep asserting, without justifying. All the information you referred me to speaks of "equality", and there is no axiom which indicates that equality is identity. Your so-called proof relied on the premise, that "=" means identical, but the axioms don't bare this out. The information you referred me to spoke of "equality" not identity, so that premise is taken as false unless you can justify it. So unless you can justify your claim, produce this information whereby it is dictated that equality is to be interpreted as identity, I will continue to conclude that you wrongly interpret these axioms.

And if you insist that this is "the conventional" interpretation, that is not a justification. All this means is that "the conventional" interpretation is wrong, as I've demonstrated.

Space can be defined in various ways, let's go with your definition (state it precisely so we can be on the same page). — leo

There is no single acceptable definition of "space". We discussed this already, there are two distinct conceptions of space. One is derived from our measurements of objects, and this produces the "space" which is occupied by an object, and the other is derived from the measurements of distance between objects, and this produces the "space" between objects. As I explained, these two conceptions of "space" are incompatible, because the former sees space as static, and the latter sees space as active.

We're also talking past each other because we don't seem to give the same meaning to the word "substance", by substance I mean some sort of liquid or solid or gas, something detectable in some way, space is none of that, to me space isn't a substance just like an idea isn't a substance. You seem to consider that anything that can be thought is substantial, that's not how I'm using the word substance here. — leo

You misunderstand the meaning of "substance" if you believe that substance must be sensible. What is sensible is the form of a thing, it's shape, colour, etc. We do not sense a thing's material substratum, what makes it a real thing, its substance. "Substance" is a concept introduced by Aristotle to validate our assumptions that the material world must be real. So it is not something whose existence we detect, we conclude through logic, that there must be "substance", or else the sensible world would be an illusion. So things which we assume to have real material existence, we say have substance.

Plenty of measurements precisely involve placing an object between or along other objects. — leo

Yes, that's true many measurements involve placing one object beside another, but there is more to a measurement than just that. And that's not relevant, what is at question here, is the fact that if a measurement is made, there is necessarily something which is measured. Why do you resist the idea that when we measure the distance between two objects, what is being measured is the space between them? This is not speaking metaphorically, because the thing being measured (space in this case) must have substantial existence or else the measurement is invalid, it's just an illusion. Therefore "space" must have real substantial existence to validate measurements of distance.

When you place a ruler along two objects, you're judging how the objects fit next to the ruler, you aren't forced to invoke an underlying space that you are supposedly measuring. — leo

What are you talking about here, measuring objects, or measuring the distance between objects? If you are measuring the objects, there is no need to assume an underlying space, the substance measured is the object itself. But if you are measuring the distance between them, you are not measuring the objects, and therefore you must assume "space" as the thing which you are measuring. Otherwise you are not measuring anything, and your measurement is not a valid measurement because there is nothing which has been measured.

No, you and some other people reify time, and you and some other people "understand" time as a dimension of space. Time doesn't have to be reified, and time doesn't have to be treated as a dimension of space. You can do that if you like (as long as you understand it's a model, otherwise you're committing a logical fallacy), but stop pretending it's a necessity. — leo

You don't seem to understand, a model must model something, or else it's not a model, just like a measurement must measure something or else it's not a measurement. Therefore it really is a necessity that the thing modelled must be real, substantial, or else the model is invalid, meaningless nonsense, because you have a model which doesn't model anything real.

Are you saying that space and time are substantial because in common usage they are treated as substantial? So if something in common usage is treated as substantial then it becomes substantial? If in common usage pink elephants on the moon are treated as substantial then there are pink elephants on the moon? Either you're committing the very fallacy of reification, or you're playing with semantics. — leo

But pink elephants on the moon are not treated as substantial, so you have no point here. Again, you don't seem to understand. The things which are treated as substantial are the things which are believed to be substantial. What other possibility is there? If time and space are treated by us as having substantial existence, then they are believed by us to have substantial existence. What more is there that I am missing? What you are missing is that it is contradictory to treat space and time as having substantial existence (as you do), yet claim to believe that they do not have substantial existence (as you do).

Whereas you know why I don't treat space and time as substantial? Because I don't see space nor time, I see objects, rulers, clocks. The concepts of space and time stem from observations of these substantial things, not the other way around, and that you don't seem to get despite me explaining it to you again and again. — leo

But you do treat space as substantial, you defined it as "the unoccupied volume between tangible objects", and spoke about measuring that volume. It just appears now, that you have a misunderstanding of what "substance" means, such that you believed that substance was necessarily something you could see. I hope you now realize that this is incorrect, we see colours, and different shapes, but we don't see substance.

Would you say that they move towards each other because space is shrinking between them? That would be again the fallacy of reification. — leo

This is false. As I explained, under your conception of "space", space is necessarily something real, substantial, so there is no fallacy of reification here. The space between the two object is shrinking, or else your measurements are invalid because they are not measuring anything.

If I wasn't looking at them moving and I only saw them at rest and I made two measurements and the second one was less, I would say that the objects have got closer to one another, I wouldn't say that some space substance has physically shrunk between them.

If you like you can say that the distance between them has decreased, or you can even say that the space between them has decreased, as long as you understand space to be a concept, an idea, a tool of thought, and not a physical thing like the objects, not a substance. Just like a distance isn't a substance, it's a concept, a tool of thought. — leo

It's fine and acceptable to talk about them being closer to each other, but then you do not mention "space". As soon as you mention "the space between them", you have referred to a real substantial thing which lies between them. What sense does it make to talk about "the space between them" unless you are actually referring to the space between them?

Also, realize that if you consider that when objects move relative to each other it's because space is shrinking or expanding between them, then in your view objects never move relative to space, they are always at rest in space, and that's surely not the concept of "space" in common usage, it's your idiosyncratic one. — leo

I don't think that anyone conceives of motions as objects moving relative to space, so I think it's you who has a rather idiosyncratic concept of "space".

The point is that the right understands that politics is about power — StreetlightX

That itself is a misunderstanding. As you seem to have taken Thrasymachus' position on justice, 'might is right', you would probably benefit from a more thorough reading of "The Republic". :"Power" can only be attributed to the will of the individual, and that's why the person who is capable of doing the most good is also capable of doing the most bad. Politics, in its true nature, involves one of these, and not the other. The idea that a party can hold power is a form of nonsense which Plato reduces to nothing other than 'mob rules'.

Mob rule is a rough sea for the ship of state to ride; every wind of oratory stirs up the waters and deflects the course. The upshot of such a democracy is tyranny or autocracy; the crowd so loves flattery, it is so hungry for honey, that at last the wiliest and most unscrupulous flatterer, calling himself the ‘protector of the people’ rises to supreme power (565).

I hear what you’re saying, but I disagree, which is another instance of us talking past each other, and you’ll probably disagree with me disagreeing, which will be yet another instance, and so on. — leo

I've provided arguments for my position, based on the definition of "space" which you gave, evidence that I'm not "talking past" you. If anyone is talking past the other, it is you, asserting that "space" as it is commonly understood, is not something substantial, in complete ignorance of what the models, and your definition of "space" indicate.

I disagree, when you put a ruler between two objects you’re not measuring space, you could simply say “this object that I call a ruler visually fits between these two objects”, no need to invoke a separate substance that is supposedly measured. — leo

Placing object Y between object X and Z, is not a case of making a measurement. This is a diversion, a ruse, or distraction created by you, in an effort to avoid the point of my argument. For me to construe this as a measurement, you'd need to produce a scale by which the degree of "fits" is being judged.

To measure is to determine the quantity, extent, or size of something. To measure the distance between two objects, which is a common practise, requires that the quantity, extent, or size of something is being determined. That something is space. To place a ruler between objects X and Z, and say that the ruler fits between objects X and Z, is not a case of measurement unless the quantity, extent, or size of something is being determined. If the ruler placed between X and Z is being used to measure, it is being used to determine the quantity, extent, or size of something. If it is not determining the extent of the space between the two, then what is it determining the size of?

Now you’re refying time. It’s the other way around, we observe change, and then we come up with the concept of time. There is no entity called “time” that we have identified that is responsible for the change we observe. We simply relate change to some reference change that we call a clock. We don’t observe “time passing”, we observe objects that we call clocks change. — leo

Of course time is reified. Time is understood as a dimension of space, and space is necessarily reified according to the concepts we use to measure it, as explained above. Therefore time is necessarily reified as well. But it's not me who is reifying these, they are already reified by the concepts we use to understand time and space. I am just explaining this fact to you. This is a fact which you are having a hard time apprehending because you seem to hold as an ontological principle, that space and time are not substantial. And, despite me demonstrating that this ontological principle is not supported by the concepts of "space" and "time" in common usage, you have provided no support for your personal ontological principle.

Your point of view implies among other things that if two objects get closer to each other it’s because space is shrinking between them. I disagree. — leo

OK, that's fine, you disagree. I already know that, because that's what you keep asserting. Now support your principles, justify your disagreement. Suppose we measure the distance between X and Z at one time, and we measure the distance between X and Z at a later time, and find that the distance is less. If this is not a case of the space between them shrinking, what is it? Don't say that it is a case of the objects moving relative to each other, because that is exactly what movement is, a change in the space between objects. I want you to justify your belief by explaining how objects could move without there being a real substantial space which changes when objects move.

Trump’s very presence and his contrast to previous politicians has forced many to think about politics again (some, it seems, for the first time in their lives), leading to a stronger left and right on the American political field. — NOS4A2

This, though, is entirely right. Trump has been an incredible force of galvanization, for the right and left alike. — StreetlightX

That "force", is a force of division. Whether a divisive force within a people is better than a unifying force within a people depends on one's attitude towards the people.

We're talking past each other here. Sure if you want let's say that there is space between objects and that objects occupy space. You agree that this space is conceptual, that it comes from measurements, either measurements between objects or measurements of objects themselves. — leo

We're talking past each other because you are not listening to what I am saying. The point I was making, is that the space which is between objects (which is how you define "space"), is apprehended, or conceived of as being substantial. When you measure, there is necessarily something which is being measured. When you measure the distance between objects that something is space.

So what does it mean to say that space "bends", or "curves", or "expands"? It simply means our measurements are changing, that is the distance between objects changes, or the shape of the objects change. It decidedly does not mean that space is not merely a concept but a tangible substance that physically bends or curves or expands and is responsible for the changing distance between objects. An object is a tangible thing, a measuring device is a tangible thing, space is not, you said it yourself it's a concept, you can't take a spoon of space, you can't boil space or cut it in half, you can't throw space, you can't lick space, ... — leo

So this is wrong, when we say that space bends, curves, or expands, we are saying that space is substantial, and these are the properties that it has. Yes, "space" is a concept, but within that concept, as necessarily implied, or dictated by the concept, is that space is something real, substantial. This can be readily understood through what I said above. When we measure, there must be something which is measured or else the measurement is meaningless. It is invalid as an actual measurement if there is nothing substantial which is being measued. So when we measure the distance between objects, we presuppose the substantial existence of "space", as the thing being measured.

Objects move and change, because time is passing. In our attempts to understand and conceptualize these changes we've come to the conclusion that space curves, bends, and expands. This is what happens to space, as time passes, and this new, more comprehensive way of understanding space has left the ancient concept, of a static space, as inadequate for the progression, and evolution of knowledge. But it is implied within this new concept of space, that space is real, substantial, as the thing with these properties.

So, when people say that planets revolve around the Sun because they follow straight lines in a curved space, that's wrong, the curved space is not the cause, it is a model, a representation, we don't detect a space substance that is physically curved, and we are not forced to invoke a curving space to model the motions we observe. To say that curved space is a cause of the motions we observe is to give an illusion of explanation and to reify space as a tangible thing. — leo

Everything that we say about things is a model, or representation, that's just a fact of how we speak. But that doesn't mean that we are not speaking about, referring to, what we believe are real, substantial things. One might say "the sky is blue", and that's a model or representation, but 'the sky" is referred to as a real thing. You might say, that "the sky" is not a real thing, by your ontological principles, but in that model, the sky is a real thing, the thing referred to as being blue. It would require that you produce another model, one which doesn't hold 'the sky" as the real thing being referred to, in order to support your ontological principles. But it's inconsistent, and contradictory to use the model, and also claim that the sky is not a real thing.

Likewise, you use a model which represents "space" as a real, substantial thing, the thing that exists between objects, which is measured when we measure distances, but you claim to hold as an ontological principle that space is not real or substantial. Well, to support your ontology, you need a model of "space" which does not represent space as something real, substantial. What is it that exists between objects, that is being measured when we measure distance, an aether o something? In other words, you might insist that we ought not reify space, but this is irrelevant to the fact that the model you use actually does reify space.

And as I explained, that's the same as saying that a binary star is full of empty space, rather than simply saying that it is two stars orbiting one another. Just because we call two stars orbiting one another a "binary star" and can treat it as one whole, does not suddenly imply that space is a substance that can curve or expand and that it refers to anything more than the unoccupied volume between things. — leo

That analogy doesn't provide a solution to the problem. The problem is that not only is there space between objects, but objects also occupy space. You might say that the only real objects are point particles, which occupy no space, but then you rob objects of their reality, only to hand it to space.

Well on the one hand we have the space that we do see, the unoccupied volume between tangible objects, that's where our very notion of space comes from. — leo

I think you have this wrong, not only do we not "see" space (it is conceptual), our notion of space comes from measuring objects, and this means it is derived from the "space" occupied by things, not the space between things. Consider the development of ancient geometry, the right angle was developed for the purpose of measuring land for example, and the principles of a "circle" are the principles of a thing.

But history has shown that when we apply these principles produced for the purpose of measuring things, to measuring the "space" between things, there is a problem. That problem is that things are moving in relation to each other. This adds another "dimension" to the problem of "space", because "space" is now not the static area occupied by a thing, it is the changing distance between things.

The issue, as I pointed out earlier is that the "space" occupied by a thing is fundamentally different from the "space" between things. The two concepts of "space" are incompatible because the space occupied by a thing is static and the space between things is changing. When we move to allow that the thing is changing, and therefore the space occupied is not static, we describe the changing thing, as parts moving relative to each other. But then we're not talking about the original "thing" anymore, as the parts are now things in themselves, the subjects of discussion.

So I'd reverse your order of space 1 and 2

So what I was doing, is that I used the notion of space1 to explain that when the shape of space1 changes, it's merely that the tangible objects (which define the very shape of space1) are moving, so we don't need to say that space1 is a substance that curves or expands and that is responsible for making the objects move. When we talk of space1 curving or expanding, we're not doing anything more than describing the motions of the tangible objects, there is no need to reify space1 as a substance. — leo

You can't do this with "space 1" though. In space 1, space is the thing measured, so if the distance between objects changes, then the measurement changes, therefore space, as the thing measured, changes.

Then usually the notions of space1 and space2 are conflated, that is usually we imagine that the tiny invisible particles that make up a tangible object are real things and not just theoretical entities, so in that context we can apply the same reasoning as in the paragraph above to say that the space between these particles refers merely to the unoccupied volume between them, that it is not a substance that has any causal influence on the motions of these particles. — leo

So this is false too. You are actually removing "substance" from the things, making them point particles, and making space, as the thing measured, into the substance. Since space is the thing measured, you cannot interpret this model as saying that space is not substance.

Streetlight thinks we ought to change the topic of the thread to discuss politics rather than character. But we're the peanut gallery here, and we like to think we're judging the politician's character, not the politician's policies. There's no fun in the latter.

- points at which one might actually intervene to make a difference i.e. engage in politics and attempt to excercise agency. — StreetlightX

That takes character, to jump in and intervene, make a political difference. Trump did it, he's got character. The reasons for doing it define the character, good or bad.

You can also talk of the center of gravity of two distinct bodies such as binary stars, and treat them as one cohesive body, but it's not necessary, you can simply model the motion of each star individually without referring to a center of gravity, which is a tool of thought and not a tangible thing. So I don't agree that talking about the center of gravity of a body implies that space is a tangible substance that can curve or expand, in principle we could also model each part of the body individually and never talk of a center of gravity. — leo

As I explained, a body is full of empty space, and that empty space is treated as part of the body, and therefore substantial. You might model the motion of a body without referring to its centre of gravity, but it is implicit within the way that the multitude of parts which compose "the body", is treated as one whole.

If we define space as the unoccupied volume between tangible objects, then when the shape of that volume changes it's simply that the tangible objects are moving, we don't need to say that the volume is made of an underlying substance that is changing shape and dragging the objects with it. — leo

This is not an acceptable definition for physicists though, because physics deals with objects which are very tiny and therefore not tangible. A tangible object is made up of parts which are not tangible. And even if you define "tangible" in such a way that all these tiny parts are said to be tangible, there is the issue of having to deal with the "space" within a large tangible object. The "space" within an object allows its parts to be moving.

The "space" within tangible objects is outside your proposed definition of "space". If we say that when we are talking about its constituent parts, the "space" within the whole is "space", and when we are talking about the object as a whole, it is not "space", then the same area is treated in one context as "space", and in another context not as space, and this is contradictory. So we cannot define "space" in that way without the consequence of contradiction. .

You can have contact action without assuming space to be a concrete substance. As an analogy, if I throw a ball at you and it hits you there is no spooky action-at-a-distance, the contact action occurs when the ball hits you. In the case of gravity we can assume there are things traveling between bodies attracting one another, which have an influence when they reach the bodies. — leo

The problem is not so simple though. One object hitting another is nothing but a transferal of force or energy from on solid body to another. But when we look at what constitutes a solid body, it is tiny parts, with space between them. So we need to account for how the tiny parts of one body interact with the tiny parts of another body, as if the two bodies are each a coherent, massive whole, instead of the tiny parts simply interacting with each other, as independent bodies.

Now, since the space occupied by a massive whole is mainly empty space, with tiny parts precisely positioned to make a whole massive body, all that "empty space" must be modeled as part of the body. This is why the centre of gravity (or, centre of mass) is an important concept in physics, it allows that numerous particles with various spatial relations, can be treated as one cohesive body. However, this way of modelling things necessarily reifies the space within that body, as part of the body. and clouds the issue of how the parts of the body interact with the parts of another body, in the transferal of force. The concept of placing the force at a point has literally been abused by physicists to produce nonsensical things like point particles.

But it is wrong to say that just because we can model what we do observe as perturbations of an underlying space, then that implies that space really is a substance curving or expanding or stretching, it's a theoretical model out of many possible, it's not something we actually observe or detect, and it's not the only way to explain what we do observe. — leo

I believe that this is an incorrect assumption, and that there is really no way to adequately or accurately model motions and interactions of bodies without representing "space" as a real underlying substance. As described above, there is no way to even account for the existence of a body without representing its internal "space", as part of the body, and therefore substantial.

Clouds are lonely?

You deliberately re-quoted exactly the line that I apologized for, explained as a typo, and corrected in my previous post. Why? You do know you're strenuously arguing against a typo for which a correction has already been issued, don't you? — fishfry

It couldn't have been a typo because you continued afterward, to make the same mistake. Look:

I know of no instance in which mathematical equality is anything other than set identity and logical identity. — fishfry

You claimed that in ZFC they misuse the law of identity in some way — fishfry

No, I said that equality in ZFC is not based in the identity of the law of identity. I explained why this is the case.. You insisted that the equality of ZFC is based in identity, so I asked you for a citation of a law of identity which ZFC is based in. I'm still waiting.

It's not a matter of what people " think they know" but of the common understanding that meanings of terms are based upon. — Janus

It is exactly a matter of what they think they know. The problem is that we take some things for granted, because they are assumed to be "the common understanding", locked up into the way that we use the words. But the common understanding is often misunderstanding. it's almost like a fashion, we accept something as true because others do. This is evident in phrases like "the sun rises", and "the sun sets". These are phrases which used to represent the common understanding, things which people took for granted thousands of years ago, which we now know as misunderstanding, because we recognize that the earth rotates.

This is the important point of Plato's cave allegory, the philosopher sees beyond the common understanding (which is really misunderstanding) to the true reality.

The point is that human knowledge is grounded in things which we take for granted. But in reality these "things", (Wittgenstein's bedrock or hinge propositions) are the extreme limits of human knowledge, and they actual mark off, or even represent the unknown. When there appears to be a limit to what can be known about something (beyond this point appears to be beyond our intellectual capacity), we establish a principle which marks that limit, and allows us to work around that unknown element.

So we find these principles in examples like Aristotle's "matter", and Newton's first law of motion. Notice that we do not at all understand what matter is, or what inertia is, but these principles allow us to work around this area of the unknown, that aspect of reality which appears to be beyond our intellectual capacity. These principles are very useful, and lend themselves to "the common understanding". However, we know from quantum mechanics that Newton's law of inertia does not properly represent the temporal continuity of physical existence. So this principle, Newton's first law, is something we take for granted, and it has become the common understanding, but it really is a misunderstanding, because it creates the illusion that we think we know what we do not really know, as the unknown lurks behind this principle.

Interestingly, 'matter' (hyle) is derived from the same root as 'mother', with the connotation of it being the passive component. The 'active' component is, on the one hand, the 'active intellect', when individuated, or intellect in general. — Wayfarer

We may have discussed this briefly before. Plato makes this reference to the female aspect, in Timaeus, referring to ancient myths. He might be criticized for being sexist when he describes matter or "the receptacle", in this way, but he is really just referring to this ancient wisdom, citing myths, to support what he is putting forward as the relationship between universal forms, and particular material objects.

In their discussion in the Timaeus they find it necessary to posit "matter" as a principle of individuality. However, the matter is necessarily passive, as being merely a receptacle for the active form which will in-form the matter, determining what type of thing will be generated. It's really just an analogy using the ancient understanding of sexual reproduction, but it's not a very good analogy because it portrays the mother as completely passive in determining the traits of the off-spring, and even the ancient Greeks, though they gave priority to a good sire, knew by this time that this was not true.