Answer by Asaf Karagila for Why are the Separation axioms 'too weak to...
Suppose that you work with the following naive theory:Extensionality, so you can say when two sets are equal;Comprehension, so you can say that if you can describe a collection, then it is a set; and...
View ArticleAnswer by Dan Christensen for Why are the Separation axioms 'too weak to...
I think he just means that simply replacing Full Comprehension with Restricted Comprehension is not enough. Given sets $X$ and $Y$, you could infer the existence their union $X\cup Y$ using Full...
View ArticleWhy are the Separation axioms 'too weak to develop set theory with its usual...
I was reading Jech's Set theory; there after introducing Russell's Paradox, he asserted:The safe way to eliminate paradoxes of this type is to abandon the Schema of Comprehension and keep its weak...
View Article
More Pages to Explore .....
