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Zermelo-Fraenkel Axioms for Set Theory

The Zermelo-Fraenkel Axioms for Set Theory, or just `ZFC' for short, include the following nine axioms.

Axiom 7.1 (Axiom of Extensionality)  

\begin{displaymath}\forall x \forall y (\forall z (z \in x \leftrightarrow z \in y)
\rightarrow x = y)\end{displaymath}

Axiom 7.2 (Axiom Schema of Separation)  

\begin{displaymath}\forall x_0 \ldots \forall x_{n-1} \forall x \exists y \foral...
...\leftrightarrow (z \in x \wedge \phi(z, x_0, \ldots,
x_{n-1})))\end{displaymath}

Axiom 7.3 (Pair Set Axiom)  

\begin{displaymath}\forall x \forall y \exists z \forall w (w \in z \leftrightarrow
(w = x \vee w = y))\end{displaymath}

Axiom 7.4 (Sum Set Axiom)  

\begin{displaymath}\forall x \exists y \forall z (z \in y \leftrightarrow \exists w
(w \in x \wedge z \in w))\end{displaymath}

Axiom 7.5 (Power Set Axiom)  

\begin{displaymath}\forall x \exists y \forall z (z \in y \leftrightarrow \forall w
(w \in z \rightarrow w \in x))\end{displaymath}

Axiom 7.6 (Axiom of Infinity)  

\begin{displaymath}\exists x (\emptyset \in x \wedge \forall y (y \in x \rightarrow
y \cup \{y\} \in x))\end{displaymath}

Axiom 7.7 (Axiom Schema of Replacement)  

\begin{displaymath}\forall x_0 \ldots \forall x_{n-1} (\forall x \exists^{=1} y
...
...w \exists x (x \in u \wedge
\phi(x, y, x_0, \ldots, x_{n-1}))))\end{displaymath}

Axiom 7.8 (Axiom of Choice)  

\begin{displaymath}\forall x ((\emptyset \not\in x \wedge \forall u \forall v ((...
... \forall w (w \in x \rightarrow
\exists^{=1} z z \in w \cap y))\end{displaymath}



 

Selmer Bringsjord
1999-04-19