- #351
matt grime
Science Advisor
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You've still not explained what {.} means, but we'll presume that it is an arbitrary set of cardinality 1, let us take an example: we can all agree on the finite cardinals, and their existence. So {1} is a set with one element. Demonstrate that this set can ONLY be defined by a tautology, further, explain how the axiom of abstract/representation relations is used in the implication you claim (it is not obvious), moreoever, define what an internal part is. also explain why {1,2}n{1,3} does not also define a singleton set, or is that a tautology? If so please explain what you think tautology is, and give an example defining some set that is not a tautologous statement, and which must therefore be a non-singleton set.
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