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visits member for 1 year, 11 months
seen Aug 27 at 1:03

Just a bitch


Aug
22
comment How can I distribute 15 pennies (1 cent) and 17 nickels (5 cents)?
1: 6p+8n, 2:3p+3n, 3:3p+3n, 4:3p+3n
Aug
18
comment Following the Von Neumann definition of ordinal, why $V$ is not a set?
Does "the supremum of a set of ordinals" assume that the collection is a set or only that the elements are sets?
Aug
18
comment Following the Von Neumann definition of ordinal, why $V$ is not a set?
Ok, I'll try to think about it, but still do not get what it is wrong. I might ask a different but related question tomorrow. Thanks!
Aug
18
comment Following the Von Neumann definition of ordinal, why $V$ is not a set?
But is not $Vα^{Ord}$ α∈Ord as defined above, a set of ordinals? (I mean, each one is an ordinal)
Aug
18
comment Following the Von Neumann definition of ordinal, why $V$ is not a set?
OK, I believe you. Can't you tell me what is wrong in the argument? (it says that the supremum is an ordinal)
Aug
18
comment Following the Von Neumann definition of ordinal, why $V$ is not a set?
because wikipedia says so? quote: "... every set of ordinals has a supremum, ** bold the ordinal obtained ** by taking the union of all the ordinals in the set (this union exists regardless of the set's size, by the axiom of union)".
Aug
18
comment Following the Von Neumann definition of ordinal, why $V$ is not a set?
I want to understand what is wrong in the original argument. Is it then that"... every set of ordinals has a supremum, the ordinal obtained by taking the union of all the ordinals in the set (this union exists regardless of the set's size, by the axiom of union)" is wrong? is it true only for a finite union?.
Aug
18
comment Following the Von Neumann definition of ordinal, why $V$ is not a set?
I wonder if instead of $V=\bigcup_{\alpha} V_{\alpha}$ we define $V_{Ord}=\bigcup_{\alpha} V_{\alpha}^{Ord}$ where $V_{\alpha}^{Ord}$ is the ordinal of the same cardinality of $V_{\alpha}$. In this case $V_{Ord}$ is a set, right?
Aug
18
comment Following the Von Neumann definition of ordinal, why $V$ is not a set?
No, I did! but that was wrong and I am not sure if your answer was pointing at that or not. Sorry for the confusion.
Aug
18
comment Following the Von Neumann definition of ordinal, why $V$ is not a set?
Asaf's answer was more direct, the wrong assumption was that the sets V_alpha were ordinals. I am not sure if you stated that, perhaps you did but I didnt get it. Thanks anyways.
Aug
18
accepted Following the Von Neumann definition of ordinal, why $V$ is not a set?
Aug
18
comment Following the Von Neumann definition of ordinal, why $V$ is not a set?
I understand the argument that V cannot be a set. I am asking why it does not contradict the Von Neumann definition. Or at least what is wrong in the quoted text.
Aug
18
asked Following the Von Neumann definition of ordinal, why $V$ is not a set?
Aug
18
accepted Is the function $|V_{\alpha}|$ normal?
Aug
18
asked Is the function $|V_{\alpha}|$ normal?
Jul
17
awarded  Altruist
Jul
17
comment The standard role of intuitive numbers in the foundations of mathematics
the answer is not good (ACTUALLY A PIECE OF CRAP) but I am giving the bounty to the worst answer, so you win! congratulations!
Jul
17
revised Proof correctness problem
added 175 characters in body
Jul
17
answered Proof correctness problem
Jul
15
comment “I have found a dead body on my car.”
sorry, Roy's answer appeared again!