Second-order logic and Russell's Paradox

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I know that in first-order logic the following holds [see e.g. George Tourlakis, Lectures in Logic and Set Theory. Volume 2: Set Theory (2003), page 121] :

$\vdash \lnot ∃y \ ∀x \ [A(x,y) \leftrightarrow \lnot A(x,x)]$,

for any formula $A(x,y)$.

I assume that this result "transfers" to second-order logic.

A simple instance of s-o comprehension schema is:

$∃X \ ∀x \ [\varphi(x) \leftrightarrow X(x)]$

where $X$ may not occur free in $\varphi(x)$.

Thus, with $\varphi(y) := ∀x \ [A(x,y) \leftrightarrow \lnot A(x,x)]$, we get:

$\vdash ∃X \ ∀y \ [∀x \ (A(x,y) \leftrightarrow \lnot A(x,x)) \leftrightarrow X(y)]$.

May we "cook together" the two results to conclude with ?:

$\vdash ∃X \ \lnot ∃y \ X(y)$


Note : motivated also by this Wiki's talk-page.

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You may do that, but I don't think it buys you anything that you don't get by letting $\varphi(y)$ be any odd contradiction such as $A(y)\land\neg A(y)$.