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Can you define an ordered set using something like Kurwatowski's
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Can you define an ordered set using something like Kurwatowski's definition of ordered pairs?
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pls responds
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>>7904313

Who is she?
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>>7904624
she's old now, like 30 years old
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Very old
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Too old
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>Kurwatowski
remove this, I ask you kindly
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>>7904873
merely a typo :&)
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Any poset? I think not. Linearly ordered set? Yes
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>>7904890
how
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>>7904624
Rose Wolfe, newfriend
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>>7904624
>she
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>>7904313
I guess that you're thinking the ordered pair (a,b)={{a},{a,b}} as a poset using the order given by x<y iff x belongs to y so your idea is to find for every poset (X,<) a set A such that with the order given by x<y iff x belongs to y the poset A turns to be isomorphic to (X,<).
If what I just said is what you want then you can use the Von Neumann definition of ordinal number to find for every well ordered set the set A with the property, for a general poset (or even a general linearly ordered set) I have no idea if the set A exists.
Maybe >>7904890 can help in the linearly ordered case.
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>>7905069

Does she have nudes?

>>7905081

What is the meaning of this statement?
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>>7904313

she has the face of cumberbatch
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>>7905286
>>she
>what is the meaning of this statement
Could you make it any more obvious?
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>>7905286
fuck off rose is an pure maiden
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>>7904313
>Kurwatowski
Ty downie jebany
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how is rose becoming a sci meme in 2016
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>>7905561
Rose is /sci/
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>>7904313

source?
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>>7904313

Who is this scrotum totem?
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>>7904313
>>7907455
Obviously? The set of all [math] \{\{x\}, \{x,y\}\} [/math] such that [math]x<y[/math] encodes the order. After all, as you said, [math]\{\{x\},\{x,y\}\} [/math] can be taken as a definition of [math](x,y)[/math].
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>>7907458
I think you misread the question. I'm talking about defining ordered sets/lists by extending {{x},{x,y}}.
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>>7905266
For a total order you can just use [math]\{ \{ x \in X | x \le y\} | y \in X \}[/math].
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>>7907521
Actually make that [math]\{ \{ X_i | i \in I \land i \le j\} | j \in I \}[/math] where [math]I[/math] is the totally ordered index set. For pairs, [math]I[/math] would be [math]\{1, 2\}[/math].

And I guess I need to think about whether this would have the expected properties.
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>>7907521
>x <= y
I don't get it
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>>7907537
>And I guess I need to think about whether this would have the expected properties.
Starting with whether the mapping from functions of [math]I[/math] to these things is injective.
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"define an ordered set using"

Can you please say clearly what you're asking?
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>>7907537
>>7907547
And it fails even for triplets, that was quick.
(1, 1, 2) -> {{1}, {1,2}}
(1, 2, 2) -> {{1}, {1,2}}
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>>7907565
>>7907463
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>>7907537
>>7907547
>>7907569
kek
try again
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>>7907463
Well, that's pretty vague, but probably anything that would be sufficiently "like" Kuratowski would work only for well-ordered sets.

Certainly, the natural generalization [math] \{ \{x \} , \{x,y \}, \{x,y,z\}, \ldots \} [/math] (potentially extended transfinitely) can code only well-ordered sets.
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>>7907541

Underrated.
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