Question About Hilbert's Hotel

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The 2n-1 equation is not relevant. You can put the one to one correspondence which you believe in together without it, no? So it adds nothing. Yet I disagree with the one to one correspondence at any level. 1 2 3 4 5 6 7 8 9 10 do NOT correspond to 1 3 5 7 9. That’s reality
 
Gamow and Cantor both used sleight of hand to convince people of their irrational thesis. But careful concentration shows there error.
 
The 2n-1 equation is not relevant. You can put the one to one correspondence which you believe in together without it, no? So it adds nothing. Yet I disagree with the one to one correspondence at any level. 1 2 3 4 5 6 7 8 9 10 do NOT correspond to 1 3 5 7 9. That’s reality
For the set of natural numbers and the set of odd numbers, 2n-1 is the relationship that yields a one-to-one correspondence between them. For other sets, a different formula (not equation – an equation has an equals sign in it, as the name indicates) would serve the same purpose.

And I have agreed numerous times thar {1, 2, 3, 4, 5, 6, 7, 8, 9, 10} cannot be placed into one-to-one correspondence with {1, 3, 5, 7, 9}. No one has claimed that it can, since one set has twice as many members as the other. On the other hand, {1, 2, 3, 4, 5, 6, 7, 8, 9, 10} does correspond one-to-one with {1, 3, 5, 7, 9, 11, 13, 15, 17, 19}. You are hung up on stopping at 10 both times, when the question we are interested in has nothing to do with that but is instead all about how many members there are.

Usagi
 
Gamow and Cantor both used sleight of hand to convince people of their irrational thesis. But careful concentration shows there error.
Do you honestly think that the best explanation of the situation here is that your “careful concentration” has uncovered an error or deception that the vast majority of people who devote their lives to studying this topic have never noticed? If it were that easy a mistake to uncover, doesn’t it stand to reason that mathematicians would long since have discarded this “irrational thesis” and moved on to something else?

Usagi
 
Do you honestly think that the best explanation of the situation here is that your “careful concentration” has uncovered an error or deception that the vast majority of people who devote their lives to studying this topic have never noticed? If it were that easy a mistake to uncover, doesn’t it stand to reason that mathematicians would long since have discarded this “irrational thesis” and moved on to something else?
Drs Dunning and Kruger have a great deal to say on this point, I think.

rossum
 
For the set of natural numbers and the set of odd numbers, 2n-1 is the relationship that yields a one-to-one correspondence between them. For other sets, a different formula (not equation – an equation has an equals sign in it, as the name indicates) would serve the same purpose.

And I have agreed numerous times thar {1, 2, 3, 4, 5, 6, 7, 8, 9, 10} cannot be placed into one-to-one correspondence with {1, 3, 5, 7, 9}. No one has claimed that it can, since one set has twice as many members as the other. On the other hand, {1, 2, 3, 4, 5, 6, 7, 8, 9, 10} does correspond one-to-one with {1, 3, 5, 7, 9, 11, 13, 15, 17, 19}. You are hung up on stopping at 10 both times, when the question we are interested in has nothing to do with that but is instead all about how many members there are.

Usagi
When I said that the 2n-1 relation was arbitrary, I didn’t mean that 2 times 3 minus 1 wasn’t 5, but that its function in your argument was faulty. Just because lots of people believe it don’t make it true, nor that other things they believe are false. Once people were considered a fool to believe that geocentrism was false. 2n-1 can’t crunch 1 3 5 7 9 to line up with 1 2 3 4 5 6 7 8 9 10 and that is the essence of my argument. 1 2 3 4 5 6 7 8 9 10 is larger, and it **will continue to be **as you multiply 1 3 5 7 9 and 1 2 3 4 5 6 7 8 9 10 to infinity.
 
When I said that the 2n-1 relation was arbitrary, I didn’t mean that 2 times 3 minus 1 wasn’t 5, but that its function in your argument was faulty. Just because lots of people believe it don’t make it true, nor that other things they believe are false. Once people were considered a fool to believe that geocentrism was false. 2n-1 can’t crunch 1 3 5 7 9 to line up with 1 2 3 4 5 6 7 8 9 10 and that is the essence of my argument. 1 2 3 4 5 6 7 8 9 10 is larger, and it **will continue to be **as you multiply 1 3 5 7 9 and 1 2 3 4 5 6 7 8 9 10 to infinity.
I can see where your conceptual error is. I wish I had a blackboard, that would make this so much easier. I’ll try here.

N 2N-1​

1 1 1
2 2 3
3 3 5
4 4 7
5 5 9
6 6 11
7 7 13
8 8 15
9 9 17
10 10 19

We’re just filling up sets, here. The # is how many elements we’re up to. N is the set of all whole numbers. 2N-1 is the set of all odd numbers. If you let N go to #10, you need to let 2N-1 go to #10 also. Otherwise you’re showing the full spread of one set, and half the other. Your argument is wrong because you can’t show that N will be bigger than 2N-1 (when taken to infinity). In order to do so, you need to show an instance where N will have more elements in it than 2N-1. When #=20, both will have 20 elements. When #=1,000,000, both will have 1,000,000 elements. When #=x both will have x number of elements. You can’t just admit numerals between 1-10 and consider that the pattern for the entire set. That’s like being bitten by one dog, and deciding that all dogs forever are mean and will bite.
 
I’ll tell you what an infinite set is; it’s the number of times you would have to show Thinkand (fail to)Mull that Cantor’s argument is logical and true and it doesn’t matter whether you count by integers, odd numbers, tens, or googles. They will all form an infinite set, aleph (null).

TaM, you’re all alone on this one!!!

Yppop
 
“If you let N go to #10, you need to let 2N-1 go to #10 also.” This is not true. By bring the infinity of odd numbers closer to 0 by filling in the gaps from the even numbers, you still leave an infinity ahead of the odd numbers from the gaps of the even numbers. Its boggling, that that is what YOU are trying to do, not me. I stay with the obvious logic that 1 2 3 4 5 6 7 8 9 10 is larger than 1 3 5 7 9, and WILL CONTINUE TO BE as you multiply 1 3 5 7 9 and 1 2 3 4 5 6 7 8 9 10 to infinity.

Mull on why I put “will continue to be” in capital. Maybe you’ll see what I’m saying
 
Yes, it seems intuitive that the infinite set of natural numbers must be larger than the infinite set of odd numbers – perhaps even infinitely larger, since it contains all the odd numbers plus all the even numbers. That was also my reaction when I first heard of this notion.

However, what seems intuitive is not always what is true, especially when dealing with phenomena that are outside of everyday experience like infinite sets.

As for the correspondence thing, think about how you would go about counting the odd numbers. 1 would be the first odd number. 3 would be the second, not the the third, right? Even though the set of odd numbers does not itself contain the number 2, the numbers you’re using to count the odd numbers still go 1, 2, 3, right? That’s just how counting thIngs works. The set of letters A through Z has NO members in common with the counting numbers, but I am still allowed to pair A with 1, B with 2, and so on in my effort to determine that there are 26 of them.

That is exactly what we are doing when we pair up the natural numbers with the odd numbers in pairs of n and 2n-1. Of course 2 and 4 and 6 aren’t odd numbers, but there is still a second odd number (3) and a fourth odd number (7). That is what this means:

1 1
2 3
3 5
4 7
5 9
6 11
7 13
8 15
9 17
10 19

We are not compressing anything or somehow cheating to pair the numbers up that way. That is just how you count things. And we can find the thousandth or millionth or googol-th odd number the same way. That method never stops working.

Usagi
 
But the method is faulty for two reasons. You have

1 1
2
3 3
4
5 5
6
7 7
8
9 9
10

You method puts the 3 to 2, the 5 to 3, 7 to four, ect., but** it is forgetting 11-15 in the first column**. See my point?? You have 1 2 3 4 5 6 7 8 9 10 being greater than 1 3 5 7 9. When you multiply these sets to infinity, you have an equal number of such sets, but there are more units in the first, because 1 3 5 7 9 don’t have a one to one correspondence to 1 2 3 4 5 6 7 8 9 10

Also, your method could be used to make ANY two infinities seem equal. Since you believe there is such a thing as unequal infinities, this method is not right
 
No. We have shown that the infinity of the reals does not equal the infinity of the naturals.
I don’t disagree that that the infinity of reals are greater, but the method used by Usagi would prove otherwise if it was valid. Read my last post, and then you see he is trying to count to infinity
 
I don’t disagree that that the infinity of reals are greater, but the method used by Usagi would prove otherwise if it was valid. Read my last post, and then you see he is trying to count to infinity
No. A slight variation on the method used by Usagi proves the opposite.
 
But the method is faulty for two reasons. You have

1 1
2
3 3
4
5 5
6
7 7
8
9 9
10

You method puts the 3 to 2, the 5 to 3, 7 to four, ect., but** it is forgetting 11-15 in the first column**. See my point?? You have 1 2 3 4 5 6 7 8 9 10 being greater than 1 3 5 7 9. When you multiply these sets to infinity, you have an equal number of such sets, but there are more units in the first, because 1 3 5 7 9 don’t have a one to one correspondence to 1 2 3 4 5 6 7 8 9 10

Also, your method could be used to make ANY two infinities seem equal. Since you believe there is such a thing as unequal infinities, this method is not right
I’m not forgetting 11-15 in the first column. We just didn’t show them in the sample. Remember - both of these sets are unbounded. I just showed the first 10 elements of each set… Above, you’re showing the first 10 elements of the first set, and the first 5 elements of the second set. Your problem is that you keep stopping - you’re using a bound set and trying to apply the pattern you see to the unbounded, infinite sets.

And yes, perhaps it does make any two sets seem equal. SEEM being the operative word. The diagonal argument shows that what seems isn’t true. It shows that there are infinite sets that cannot be put into a one-to-one correspondence.
 
This is just a general observation, but perhaps it will help:

People often have trouble with the notion of different sizes of infinity because the commonly used examples involve a set being compared to one of its subsets, such as the integers being placed in correspondence with the odd numbers. Such examples are counterintuitive because we tend to imagine the subset “lying inside” the larger set, so it seems absurd for the sets to be of equal size. However, correspondence is meant to offer a way of comparing two sets that may be entirely unrelated; how one may or may not be included in the other is completely disregarded.

So if we use correspondence to compare two sets, one of which contains the integers and the other contains, say, all the words representing only the odd integers (just the words, not the integers themselves), then it suddenly becomes much more intuitive. After all, why should the type of objects in the sets impact their size?
 
1 2 3 4 5 6 7 8 9 10 is greater than 1 3 5 7 9. When you multiply these sets to infinity, you have an equal number of such sets, but there are more units in the first. Please explain how any principle that forces the second set to be equal to the first cannot be used to make any two infinities equal. From how it was explained in the book it referred to, there is no such principle: you can line up some ten numbers and say they are equal because they go, from that one to one correspondence of the first ten, then to infinity
 
This is just a general observation, but perhaps it will help:

People often have trouble with the notion of different sizes of infinity because the commonly used examples involve a set being compared to one of its subsets, such as the integers being placed in correspondence with the odd numbers. Such examples are counterintuitive because we tend to imagine the subset “lying inside” the larger set, so it seems absurd for the sets to be of equal size. However, correspondence is meant to offer a way of comparing two sets that may be entirely unrelated; how one may or may not be included in the other is completely disregarded.

So if we use correspondence to compare two sets, one of which contains the integers and the other contains, say, all the words representing only the odd integers (just the words, not the integers themselves), then it suddenly becomes much more intuitive. After all, why should the type of objects in the sets impact their size?
Odd numbers all the way to infinity are a part of the whole natural numbers and are, thusly, all the way up to infinity
 
1 2 3 4 5 6 7 8 9 10 is greater than 1 3 5 7 9. When you multiply these sets to infinity, you have an equal number of such sets, but there are more units in the first. Please explain how any principle that forces the second set to be equal to the first cannot be used to make any two infinities equal. From how it was explained in the book it referred to, there is no such principle: you can line up some ten numbers and say they are equal because they go, from that one to one correspondence of the first ten, then to infinity
(1) If the set of all whole numbers and the set of whole odd numbers are of different sizes, then they will not be able to be put into a one-to-one correspondence.
(2) The sets of all whole numbers, and all whole odd numbers can be put into a one-to-one correspondence.
(C) By modus tollens, The set of all whole numbers and the set of all whole odd numbers are not of different sizes.

This argument is valid. Do you dispute the premises?
 
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