I'll be giving a small talk to the graduate students of my university on the topic of "counter-examples" and my first counter-example is Russell's paradox.(adsbygoogle = window.adsbygoogle || []).push({});

I want to put the theorem in context, but admitedly, I have no idea what I'm talking about when it comes to logic and set theory. I want to know if what I wrote is not too much nonsense.

I first cite the definition of set given by Cantor:

"By a "set" we mean any collection M into a whole of definite, distinct objects m (which are called the "elements" of M) of our perception or of our thought."

Then I say that this vague definition leads to paradoxes and presents Russell's paradox.

Then I say that it is paradoxes of this kind that led mathematicians to look for an axiomatic theory of sets. I say that the commonly used set theory today is that of Zermelo and Fraenkel, in which the problematic "set" in Russell's paradox is not one in the ZF theory. However, I add, according to the works of Gödel, it is impossible to determine if the ZF set theory is or is not free of pardoxes.

Given that what I wrote is not wrong, do you have suggestions for improvements or things I could add?

Thanks!

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# Russell's paradox, ZF and Gödel's undecidability

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