/sci/ - Science & Math

>>14479727
the first half of that statement has literally no logical connection to the latter half
it's a literal non-sequitur

Tfw scared to take an iq test

>>10067874
>femanon here

How many of you never bothered do check this?

Let [math]X=\{Y:Y\not \in Y\}[/math].
[The set of all sets not members of themselves]
1. if [math]X \in X[/math] then [math]X \not \in X[/math] is false and [math]X \not \in \{Y:Y\not \in Y\}=X[/math].
2. if [math]X \not \in X[/math] then [math]X \in \{Y:Y\not \in Y\}=X[/math].
3. [math]X \in X[/math] iff [math]X \not \in X[/math] follows.

The statement [math]X \in X[/math] then is both true and false,
which makes naive set thoery unsuitable without proper precautions.

More on this here:
https://plato.stanford.edu/entries/russell-paradox/#ERP
https://en.wikipedia.org/wiki/Russell%27s_paradox