Is Addition Really a Basic Skill?

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The discussion centers on the nature of addition and whether it can be proven. Participants argue that addition is a fundamental concept defined by axioms rather than something that can be proven in the traditional sense. The Peano Axioms are referenced as a formal system that defines natural numbers and addition, illustrating that addition is inherently intuitive and based on human understanding of quantity. The conversation highlights that while one can demonstrate properties of addition (like commutativity), the operation itself is defined rather than proven. Some participants express frustration over the vagueness of the original question about proving addition, emphasizing that mathematical operations are accepted based on axiomatic foundations rather than empirical proof. The discussion also touches on the philosophical implications of mathematical definitions, particularly in relation to set theory and the concept of individuality in counting. Overall, the consensus is that addition is a defined operation rooted in axiomatic logic, not a provable theorem.
  • #31
Wow, what a long and completely off topic post.

One cannot "prove addition". It simply doesn't make sense as a sentence in the English Language.

The OP was aksed to "prove red" and he didn't (though he appears to think he did). He gave a "definition" of red. That in itself doesn't "prove" red. What does prove even mean in that context?
 
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  • #32
matt grime said:
Wow, what a long and completely off topic post.

One cannot "prove addition". It simply doesn't make sense as a sentence in the English Language.

The OP was aksed to "prove red" and he didn't (though he appears to think he did). He gave a "definition" of red. That in itself doesn't "prove" red. What does prove even mean in that context?

I don't see the connection between "proving red" and "proving addition". Red is a phenomenon. Addition is a mathematical process (an operation on sets).

To ask that addition be "proven" is to ask that the mathematical process, or operation of addition, be logically justified. It makes sense to me, and seems like a valid question that any student should be interested in.
 
  • #33
NeutronStar said:
To ask that addition be "proven" is to ask that the mathematical process, or operation of addition, be logically justified. It makes sense to me, and seems like a valid question that any student should be interested in.


Erm, no, that isn't quite what prove means in mathematics, is it? To prove something one needs a hypothesis from which to make a deduction.

Ok, so prove minus, then, prove 3, prove composition of functions.
 
  • #34
Better still, prove eating or prove standing. After all, these too are processes or operations.
 
  • #35
NeutronStar said:
To ask that addition be "proven" is to ask that the mathematical process, or operation of addition, be logically justified.

A methematical operation need not be logically justified. There's no need for that. Once an operation/function is defined on a set, there is no justification required.

While "explain addition" would be a good question, "prove addition" makes no sense.
 
  • #36
You should start with proving proof with no idea about what must be present in a valid proof. Or perhaps not..
 
  • #37
matt grime said:
Erm, no, that isn't quite what prove means in mathematics, is it? To prove something one needs a hypothesis from which to make a deduction.

Ok, so prove minus, then, prove 3, prove composition of functions.


IF a=1+1 THEN a=2

There is a hypothesis and conclusion to prove.

Attemping to prove minus, or 3 make no sense because there is no hypothesis and conclusion. With 1+1=2 there is.

I'm not sure about the composition of functions, that could probably be put into a conditional statement and proven. But to do so we would probably need to refer intensely to the definitions of functions and composition. To prove the conditional statement above we would likewise need to refer intensely to the definitions of number (specifically the numbers 1 and 2) and the definition of operation of addition. While that may not actually "prove addition" it would at least show that addition is a valid logical concept. And in a very real sense that is proving it.

The bottom line that will be the death of this whole thing is that the operation of addition is dependent on the definition of numbers and vice versa. So the whole thing become circular. That's because of the empty set definition of numbers. If the numbers where defined on a concept of Unity then they wouldn't depend on the operation of addition for their definition and the process would no longer be circular. In other words, it would be "externally" provable via other forms of logic.

I might add that if Peano's Unity had been accepted as the foundation of the definition of number, then Kurt Gödel's incompleteness theorem would no longer apply to mathematics because mathematics would no longer be a self-contained logical system.

Drcrabs is either going to have to accept the axiomatic methods of mathematics or prove to the mathematical community why it is flawed. The former is way easier. :biggrin:
 
  • #38
Nonsense!
You INTRODUCE the mathematical symbol "2" by defining
2=1+1
You've got some silly, unmathematical preconception about what "2" is; get rid of that.
 
  • #39
arildno said:
Nonsense!
You INTRODUCE the mathematical symbol "2" by defining
2=1+1
You've got some silly, unmathematical preconception about what "2" is; get rid of that.

You may very well be correct. But if I have an unmathematical preconception about what "2" is I'm afraid that you'll have to blame that on the educational institutions that I've been taught by.

I was introduced to the idea of number in both kindergarten and in early grade school using a concept of collections of things (sets). The idea of "2" is ingrained in my intellect as the quantity than after having removed a quantity of 1 there is only 1 remaining. (that's actually backwards from the way it is taught, but I think it makes for a more rigorous definition).

I don't think of "2" as a printed numeral that we are using here to communitate the idea of two. That's just a symbol no different the the English word "T-W-O". The actual concept of "2" is a collection of individual elements such that after removing an individual element all that remains is enough "stuff" to define precisely the definition of whatever it is that it being quantified.

This may sound a bit complicated, but in reality I believe that this is everyone's everyday intuitive experience of the idea of quantity that we have come to formalise as numbers.

So based on this concept of unions of sets I have no problem at all comprehending addition. Unfortunately the most rigorous axiomatic definitions for addition do not permit this intuitive view. We must resort to Cantor's idea of collections of nothing.
 
  • #40
That isn't a proof neutron star, but even then proving 1 + 1 = 2 (which you'll see was done earlier if something so trivial can be called a proof) is not known as 'proving addition'.

We don't have to start out with the empty set in order to build Peanos axioms (I listed them above notice no mention of empty set), though it is possible to construct Peano's axioms starting with the empty set

0 = {}

0* = 1 = {0} = {{}}

(0*)* = 1* = 2 = {0,1} = {{{}},{}}

etc.

This was done by Von Neumann after Peano and there are other ways of constructing Peano's axioms.
 
  • #41
So basically after reading these pages, you are trying tell me that you actually can't prove addition?
 
  • #42
jcsd said:
We don't have to start out with the empty set in order to build Peanos axioms
Technically I disagree with that. Peano relies on the idea of 1 which has been formally accepted by the mathematical community to be defined by Cantor's definition. Therefore any reference to the number 1 is automatically a reference to the empty set by default. (In other words, Peano doesn't actually define the number 1 in his axioms, he merely uses the preexisting concept)

jcsd said:
0 = {}

0* = 1 = {0} = {{}}

(0*)* = 1* = 2 = {0,1} = {{{}},{}}
Now this has always been of interest to me. Since 1 = {0} = {{}}
and 2 = {0,1} = {{{}},{}} then the whole intuitive idea of addition as the union of sets gets blown out of the water because {{}} U {{}} does not equal {{{}},{}}. It would be {{},{}}. This is actually the way we perceive number as a property of the real universe by the way. We don't perceive 2 as {{{}},{}} we percieve it as {{},{}}. So why the need to define it in such an unnatural way?

If we define 2 as {{},{}} then it would be easy to prove addition as the union of sets. We can't prove that 1+1=2 using our current mathematical formalism because it makes no sense. :smile:

Instead we need to rely on axioms that merely state that it is true by the rule of formalisms rather than being able to prove it by logical deduction.
 
  • #43
matt grime said:
The OP was aksed to "prove red" and he didn't (though he appears to think he did). He gave a "definition" of red. That in itself doesn't "prove" red.

Yea waddup Grimey. I've noticed that you realized that i gave a definition. The purpose of the 'definition of red post' was to point out that the person who was asking me to prove red was getting off the topic
 
  • #44
Your not quite making sense, Peano did not make any refernce to the number 1 in his axioms, the only number explcitily mentioned is zero and the only properties it has are those that are defined by the axioms (though you can start with the number one in order to construct the non-negtaive integers). In Peano's system of the natural numbers 1 is just another name for 0* and the only properties it has are those that are defioned by Peano's axioms. Generically 1 is the mulpilcative identity in a semiring (I guess, as N is certainly not a ring under normal additon and multiplication), but this is something that emerges out of the defiuntion of mulpilication and additon in this set and we need not assume any preconceived notion of the number '1', other than the one given to us by our defintions.


In Von Neumann's constuction the succesor of some number n is simply n U {n}. Defining 2 as {{},{}} indeed makes no sense.
 
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  • #45
drcrabs said:
So basically after reading these pages, you are trying tell me that you actually can't prove addition?

It's not a case of 'cna't' it's just that the question makes no sense.
 
  • #46
addition may be the most basic mathematical concept. in fact, i think its safe to say that addition came first, and the numbers were defined in terms of it. is there any other way to define 2 besides 1+1? if so, then maybe there would be a way to prove addition, but i don't think there is.

also, all this talk about set theory is, in my opinion, off topic. set theory is not the only way to define addition, and it implies there is only one way it could work. its possible to imagine a universe where 1+3 is not equal to 2+2. addition is, whether you like it or not, an empirical law, from which its set-theoretic defintion was derived.

when you gave the definition of red, you were actually proving my point. addition, like the color red, is not something up for debate. it is defined, plain and simple. from a definiton, we can derive all sorts of things about the things properties, like that its commutative, or that its wavelength is 650 nm. but the defintions themselves are, in a sense, handed down by god.
(red may have been a confusing example, because it is subjective, where as we all believe addition to be objective, and based on logic. my point was that they both are so basic and innate, to prove them makes no sense.)
 
  • #47
StatusX said:
also, all this talk about set theory is, in my opinion, off topic. set theory is not the only way to define addition, and it implies there is only one way it could work. its possible to imagine a universe where 1+3 is not equal to 2+2. addition is, whether you like it or not, an empirical law, from which its set-theoretic defintion was derived.

I totally agree that addition is an empirical law of our universe. Heck, I think anyone who's been paying an attention at all to human history can clearly see that our mathematics arose from observing the quantitative property of our universe.

I totally disagree, however, that Set Theory was derived from this emperical observation. I wish it were, then addition would be provable.

Finally, concerning the idea that set theory is off topic in any discussion of addition is absurd in my humble opinion. And my reason for feeling this way is because it is through the very concept of sets (or collections of things) that the universe exhibits it quantitative nature. So even though we can disguise the idea of quantity (or addition of quantities) behind the guise of other types of logic doesn't change the fact that it can always be reduced to ideas of collections of the fundmental property of individuality for this is the nature of the universe from which the idea came.

There's just no getting around it. If we are talking about number we are talking about quantity. And if we are taking about quantity, we are talking about collections of individual things. It's a basic truth of the universe. Any concept of number that is not the concept of a collection of things is simply an incorrect concept of number. Such a concept is something other than the concept of number. So to just mention mathematics or number we necessarily have to think in terms of sets. There's just no other way to comprehend it.

True, we can write up a bunch of rules and axioms and follow them. But is that truly comprehension? Especially when we can't even prove them?
 
  • #48
Anyone who starts to talk about 'empirical laws' when talking about math proofs is most defintely on the wrong track. Maths does not claim to describe reality, the axioms of mathethamtical systems do not come from the observation of reality, they are true for the system because we define them to be true. It is pewrfectly possible to have a statement that is axiomatic in one mathematical syetm but false in another.
 
  • #49
all I am saying is that addition is so basic, it is impossible to prove within math(ie, using set theory). all you can do is define it to match empirical observations. to prove the physical law of addition is impossible, just like any other physical law. in general, id agree that math and reality are completely separate (although its naive to take this too far, since math is only useful when it helps us in the real world), but i think addition may be the point at the bottom where they meet. if anything, this is a philosopical question.
 
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  • #50
jcsd said:
Anyone who starts to talk about 'empirical laws' when talking about math proofs is most defintely on the wrong track. Maths does not claim to describe reality, the axioms of mathethamtical systems do not come from the observation of reality, they are true for the system because we define them to be true. It is pewrfectly possible to have a statement that is axiomatic in one mathematical syetm but false in another.

Had you been a student of Pythagoras he would have had you thrown overboard into the Aegean sea for making such a remark. :biggrin:

Actually I agree with you that modern day mathematicians view mathematics in a totally different way than many historical mathematicians did. And while I don't share this modern view I can't say that it is incorrect in this day and age. But what I can say is that modern day mathematics is not a correct model of the quantitative nature of our universe. :approve:

I usually put my view in a conditional statement and claim that the statement it true.

IF "mathematics is supposed to be a good model of the quantitative nature of our universe" THEN "mathematics is logically flawed".

I claim that this statement is true, although I certainly don't intend to prove it on an Internet board to a hostile audience. I'll save it for a personal lecture to people who are genuinely interested in hearing it. :smile:

I believe that most mathematicians wouldn't even be interested in hearing the proof because they would deny the hypothesis right off the bat. (This appears to be jcsd's stance, he simply doesn't believe that mathematics is supposed to be a good model of the quantitative nature of the universe and therefore any proof to show that it isn't a good model is trivial and uninteresting)

As a scientist I don't share his view. I believe that it is extremely important that mathematics properly model the quantitative nature of the universe. Therefore I am concerned with any flaws in mathematics that might make the above conditional statement true.
 
  • #51
Since we're talking about the philosophy of mathematics, I'll move this thread here.


Things have changed slightly since Pythagoras's time. :-p Science/philosophy decides what axioms you should be using, and mathematics tells you what those axioms imply.
 
  • #52
Hurkyl said:
Science/philosophy decides what axioms you should be using, and mathematics tells you what those axioms imply.
Actually I wish that was true. :approve:
 
  • #53
drcrabs said:
Yea waddup Grimey. I've noticed that you realized that i gave a definition. The purpose of the 'definition of red post' was to point out that the person who was asking me to prove red was getting off the topic


that post you refer to wasn't off topic, it perfectly illustrated that just because you can ask for something to be proven, doesn't mean the question makes sense. And when do you get to start using a familiar version of my surname?
 
  • #54
NeutronStar said:
Actually I wish that was true. :approve:


That is true.

Plus you're logical proposition that you won't prove here is trivially true since the conditional is false.
 
  • #55
NeutronStar said:
IF "mathematics is supposed to be a good model of the quantitative nature of our universe" THEN "mathematics is logically flawed".

Mathematics isn't intended to be a good model of the quantitative nature of the universe; whatever that means. I think maybe you're confusing the roles of mathematics and physics.

You've not given any justification for your belief that the foundation of mathematics, as it's currently understood, is insufficient or inconsistent. Instead, you've insisted that some facet of the current approach is wrong (like say, defining 0 first) and fail to show how it leads to either a contradiction or limitation in characterizing some useful area of mathematics. Essentially, you don't like construction of N starting from 0, but can't articulate why this is problematic; it's just a (religious) belief.

Regarding Peano, the first publication of the Peano postulates appeared in "Arithmetices Principia", which was published in 1889. In that document 1 is defined as first natural number.

Later, in 1892(?), "Formulario Mathematico" is published, which shows 0 to be the first natural number. Peano changed his approach between those two publications.

But, more to the point: The selection of 0 or 1 as the first natural number is probably only a matter of convenience.
 
  • #56
Thanks, I've always wondered why some versions of Peano's axioms start with 0 and others start with 1.
 
  • #57
CrankFan said:
You've not given any justification for your belief that the foundation of mathematics, as it's currently understood, is insufficient or inconsistent. Instead, you've insisted that some facet of the current approach is wrong (like say, defining 0 first) and fail to show how it leads to either a contradiction or limitation in characterizing some useful area of mathematics. Essentially, you don't like construction of N starting from 0, but can't articulate why this is problematic; it's just a (religious) belief.

With all due respect it wasn't my intent to prove or show anything. I was merely responding to the original poster's concern with proving addition. I simply providing information concerning that topic.

I think that there's been a general consensus among the responders to this thread that addition cannot be proven (or as some claim it is even meaningless to ask such a question). I agree that it cannot be proven using current mathematical axioms. And I also agree that within that axiomatic framework it is a nonsensical question.

I was merely pointing out that the particular axiomatic framework that is preventing the question from being meaningful was introduced rather recently (with respect to the entire history of mathematics). And that the theory that prevents it is Georg Cantor's empty set theory.

I believe that everything that I've said here is true. I believe this on solid logical grounds. I actually don't have a religious bone in my body. (maybe spiritual, but that's another topic)

I have no intent to attempt to convince people who aren't interested in this topic. The mathematical community as a whole is well aware that there are logical problems associated with set theory. This is no secret and it has been a philosophical debate for many years (not the specific empty set concept that I am referring to, but set theory as a whole logical system).

Just for a quickie I will give you concrete example of the problem,…

Originally (that is to say that before the time of Georg Cantor) a set was intuitively understood as a collection of things. Cantor then introduced the idea of an empty set. A set containing nothing.

Well, this is actually a logical contradiction right here. We have a collection of things that is not the collection of a thing. This is a logical contradiction to the very definition of what it means to be a set. Similar objections actually came up by other mathematicians at the time that Cantor proposed his empty set idea. These objections were never (and I mean NEVER) fully resolved. In fact, the significance of their implications wasn't even fully understood at the time. Nor does it seem to be fully understood today.

In any case, there are only two ways to get around this logical contradiction. One is to claim that nothing is a thing in its own right. Therefore the empty set does indeed contain a thing and there is no logical contradiction. However, that logic leads to further contradictions by the simple fact that they empty set is then no longer empty. It contains this thing called nothing. In fact, this solution was pretty much tossed out as being far too problematic. The so-called "genius" of Cantor's idea was to remove the idea of number from any connection to the idea of a thing thus making it a "pure" concept. Even Cantor did not like the idea of treating nothing as a thing.

This leaves us with the second choice,… simply change our intuitive idea of the notion of a set. A set is no longer considered to be a "collection of things". That is merely an intuitive notion that is not needed for an axiomatic system to work. Instead, Cantor suggested, let's just ignore definitions, and forget about trying to comprehend the idea intuitively and make an axiom that simply states, "There exists an empty set". He somehow sold this idea to the mathematical community and they bought into it.

However, later on (possibly even after Cantor's death, I'm really not sure on that) the mathematical community started seeing other problems cropping up. For example, there must be a distinction between a set, and an element within a set. If this distinction isn't made then 1 would equal 0.

In other words, by Cantor's empty set theory

0 = {}
1={{}}

Now if there is no distinction between an element, and a set containing a single element then there is no difference between Cantor's definition of zero and One.

I'll grant you that this may appear quite trivial but I assure you that it is not.

The problem does not exist for Cantor's higher numbers because they are more complicated combinations of sets and elements.

2 = {{{}},{}} for example. Even if the elements were to stand alone there would be not be equal with any other number. In other words, you can remove the outermost braces (which merely convey the idea of a set) without reducing the contents (the actual collection of things) to configuration that represents a different number.

By the way this is much easier to see if you actually use the symbol err to represent the empty set. Or I think modern mathematicians use the Greek letter phi.

The bottom line to all of this is that Cantor's empty set theory is logically inconsistent. It's based on a logical contradiction of an idea of a collection of things that is not a collection of a thing.

So big deal you might say. It's a trivial thing just let it go and get on with using the axioms. Well if you think like than then you truly are a modern mathematician.

This logical contradiction does exists none the less, and it really does have an effect on the logic that follows from using these logically flawed axioms.

Two things should be apparent right way. First off, there is no formally comprehensible idea of a set. If you think of a set as a collection of things you are wrong. That is an incorrect idea in Cantor's set theory. It simply doesn't hold water in the case of the empty set which is the foundation of the whole theory.

There are far reaching logical consequences to this logical contradiction. And in a very real way they are almost like relativity. Just like relativity is hardly noticeable at small velocities, so the problem with Cantor's empty set theory is hardly noticeable for quantities much less than infinity.

But just as relativity comes into play and speeds that approach the speed of light, so do the logical errors of Cantor's empty set theory come into play at quantities that approach infinity, and more precisely it affects the concept of infinity immensely.

Georg Cantor is the only human ever to start with nothing and end up with more than everything. His set theory leads to ideas of infinities that are larger than infinity. In other words, it leads to the logical contradiction of some endless processes being more endless than others. If that's not a obvious logical contradiction I don’t' know what is, yet this absurd notion has been accepted and embraced by the mathematical community.

Finally, what I have typed into this post is merely the tip of the iceberg. I'm not about to write a book on an Internet forum to try to explain what most mathematicians should already be aware of. But there are other problems associated with the empty set theory as well, and they have to do with counting, or countability.

The whole reason why Cantor introduced the idea of an empty set in the first place was to avoid having to tie the concept of number to the concept of the things that are being quantified. In other words, at the that time in history it was extremely important to the mathematical community that numbers be "pure". I might add that this was much more of a religious notion than a logical one so if we want to claim that someone was being religious rather than logical we should look at the mathematical community around the time that Georg Cantor lived!

In any case, by starting with nothing, Cantor was able to avoid having to deal with the concept of the individuality of the elements (or things) being collected. In other words, by starting with nothing he basically swept the prerequisite notion of the individuality of the objects that are being quantified under the carpet. And by doing so he has removed that constraint from any elements. In other words, in Cantor's set theory anything can be counted as an "individual" element even if it has no property of individuality. This is, in fact, the very reason why he is able to have infinities larger than infinity. He is actually counting objects that have no property of individuality yet he treats them as though they do. I can actually show the error of his ways using his diagonal proof that the irrational numbers are a larger set than the rationals say. Once you understand the whole problem concerning the property of the individuality of the elements it's a fairly obvious proof.

I don’t even know why I'm bothering to type this in actually. The mathematical community simply isn't ripe for this knowledge yet. It just isn't in the "air". I think that it will be soon though as more and more mathematician begin to study group theory where is most likely to become apparent. Some clever mathematician somewhere is bound to realize what's going on and become famous for discovering the "problem".

I think that the most important thing for mathematicians to realize is that this problem was only introduced into mathematics about 200 years ago. Compare that with the age of mathematics and we can basically say that it "just happened!".

I mean, correcting modern set theory will have no affect on things like Pythagorean's theorem, or Euclid's elements, or the vast bulk of mathematics including even calculus which came before Cantor's time. It's main impact with be in group theory. But group theory is becoming extremely important in modern science so it could end up having a big impact there.

Fortunately Cantor's illogical set theory won't affect most normal algebra or other mundane calculations, so don't expect to get tax refund checks from the government when the problem is finally corrected. The government never thinks in terms of sets anyway, they think in terms of bucks.
 
  • #58
Umm...didn't read all of that, but I believe the question makes no sense not only from an axiomatic point of view, but from a basic, language point of view.

The question makes as much sense as "prove running". This is different from asking "why does running along the (B-A) vector get you to B if you start from A ?", which while self-evident (because that's how it's defined), is at least not an improper usage of language.
 
  • #59
How do you prove proof by not proving proofs of the principles of proof?
Or something completely different..:wink:
 
  • #60
NeutronStar said:
I think that there's been a general consensus among the responders to this thread that addition cannot be proven (or as some claim it is even meaningless to ask such a question).

Right, they're saying that "prove addition" is no more meaningful a statement than "prove purple bonnet banana."

Some people, (like me), have made assumptions about what the OP wanted (probably a mistake :wink:), and sketched out a process by which the function of addition is proven to exist and retain all of the properties we intuitively expect it to have. -- these proof sketches have been ignored by the OP. No one seems to know what he has in mind when he uses the phrase "prove addition", and it's doubtful that it has any sensible meaning.

NeutronStar said:
I was merely pointing out that the particular axiomatic framework that is preventing the question from being meaningful was introduced rather recently (with respect to the entire history of mathematics). And that the theory that prevents it is Georg Cantor's empty set theory.

This is nonsense. Why should the development of some theory prevent a person from asking a meaningful question? Are you claiming that if someone was asked to "prove addition" in 1850 that it would be meaningful then? But now, in 2004 it's not meaningful? and Cantor is to blame for his apparent ability to control people's behavior from beyond the grave?

NeutronStar said:
I believe that everything that I've said here is true. I believe this on solid logical grounds.

Actually you've made many factual errors in your posts, more than I'd bother to correct. It's surprising that you say you believe everything you've said is true, shortly after you've been presented with information about Peano's postulates which contradicts your claim that he was some kind of advocate for starting from 1 as opposed to 0 ... as if any of that mattered.

NeutronStar said:
The mathematical community as a whole is well aware that there are logical problems associated with set theory.

The problems which were widely known at the time of the development of set theory do not exist in modern set theory. If you replace "set theory" in the above quote with "naive set theory" then I don't have a problem with it, but if you mean ZF by "set theory" then your statement is false.

NeutronStar said:
Originally (that is to say that before the time of Georg Cantor) a set was intuitively understood as a collection of things. Cantor then introduced the idea of an empty set. A set containing nothing.

I don't know the origin of the phrase empty set, or the first use of the term set, but I'm a little bit skeptical of taking your claims at face value given the egregious errors you've made previously about the history of mathematics.

I've only studied material which is a refinement of Cantor's work, not the original -- but I don't see how Cantor or his original work is relevant to the supposed problems of set theory as it's understood today.

NeutronStar said:
Well, this is actually a logical contradiction right here.

No it's not.

If one of the axioms asserts that sets are non-empty, then it would be a contradiction for an empty set to exist, but there is no such axiom or theorem of ZF.

NeutronStar said:
We have a collection of things that is not the collection of a thing. This is a logical contradiction to the very definition of what it means to be a set.

Again, the axioms of ZF don't assert that sets are non-empty collections of objects as you are implicitly doing. Someone recently posted a version of Berry's paradox, which "proves" that the naturals are finite. It's a very amusing "proof", the problem is that it relies on the ambiguity of natural language. Your mistake above is similar, in implicitly assuming that a collection is non empty -- of course in a formal system all of these details are made explicit, and it's not a problem.

NeutronStar said:
Similar objections actually came up by other mathematicians at the time that Cantor proposed his empty set idea. These objections were never (and I mean NEVER) fully resolved.

Can you cite these specific objections to his "empty set" theory? You seem to be hung up with the notion of the empty set, but I don't think others, even those skeptical of Cantorian set theory at the of its development had any problems with the empty set. I think the objections of mathematicians like Poincare were related to the concept of infinite sets and had nothing to do with the empty set.

When you talk of "problems never fully resolved", I'm not sure if you're talking about philosophical objections to set theory or the classical antinomies.

If you're talking about the later then all of the classical antinomies were addressed in the development of theories like ZF. It's inaccurate to say that the problems of Naive set theory exist today.

If you're talking about philosophical objections to the notion of infinite sets, well that's fine I suppose that you have an opinion, but these days, philosophical objections of this sort almost always belong to non-mathematicians, and are inconsequential.

NeutronStar said:
However, later on (possibly even after Cantor's death, I'm really not sure on that) the mathematical community started seeing other problems cropping up. For example, there must be a distinction between a set, and an element within a set. If this distinction isn't made then 1 would equal 0.

This is absurd. Every object in ZF is a set, there are no obvious problems with the theory.

NeutronStar said:
In other words, by Cantor's empty set theory

0 = {}
1={{}}

Now if there is no distinction between an element, and a set containing a single element then there is no difference between Cantor's definition of zero and One.

This is false. You're confusing the concepts of set membership and subset.

The empty set {} is a member of {{}}, it is not a member of {}. By extentionality we know that {{}} isn't the same set as {}, since {{}} contains at least 1 element not in {}.

NeutronStar said:
The bottom line to all of this is that Cantor's empty set theory is logically inconsistent.

It's strange how you keep referring to Cantor's "empty set theory".

A quick search at the following site indicates that Cantor isn't known to be the first one to use the phrase empty set or null set.

http://members.aol.com/jeff570/mathword.html

From what source are you determining that Cantor was the originator of the concept of the empty set. Note that I'm not claiming that he didn't, just that I'd like to know if this is true.

I'm not sure if Cantor's set theory can be said to be inconsistent. Certainly not as a result of the nonsensical complains you've made about the empty set. Cantor seemed to be aware of the dangers of unrestricted comprehension, apparently he wrote about it in letters to other mathematicians. That aside; whatever Cantor's theory was (consistent or inconsistent) it has no bearing on the state of set theory today. If you know of a contradiction in ZF, you can state it in the language of ZF and if can't your claim need not be taken seriously.

NeutronStar said:
So big deal you might say. It's a trivial thing just let it go and get on with using the axioms.

It's not that what you've said is trivial, it's that what you've said is incorrect. Your opinions are based on misconceptions. That you have difficulty in distinguishing between elements of a set, and its subsets tells me that you need to go over some introductory material before you're able to discuss these issues competently.
 
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