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Sam Roberts
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Yes, this is provable in NBG. To see this, let $F$ be a one-one function from $\mathcal P(A)$ into $A$. By induction we define a one-one function $G$ from $V$ into $A$ as follows. Assume $G$ is defined on $V_\alpha$, and suppose that $x\in V_{\alpha+1}\setminus V_\alpha$. Then we let $G(x) = F(G[x])$.

Sam Roberts
  • 1.2k
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  • 15