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Let $T$ be a theory formalized in first order logic with equality and membership and the additional primitive constant symbol $W$, with the following axioms:

  1. Extensionality: $\forall z (z \in x \leftrightarrow z \in y) \to x=y$

  2. Class comprehension: if $\phi$ is a formula in which $x$ doesn't occur free, then all closures of: $$\exists x \forall y (y \in x \leftrightarrow \phi \land \exists z (y \in z) ) $$; are axioms.

    Define: $x=V \iff \forall y (\exists z (y \in z) \to y \in x)$

  3. Sub-world: $W \in V$

  4. Resemblance: if $\varphi^X$ is a formula in prenex normal form, whose matrix is in $L(=,\in)$, and each variable in its prefix must appear as bounded either $\in X$ or $\subseteq X$, then: $$\varphi^V \leftrightarrow \varphi^W $$, is an axiom.

  5. All axioms of "$\sf ZF + \text {CH fails everywhere}"$ relativized to $W$.

Define: $x=V \iff \forall y (\exists z (y \in z) \to y \in x)$

  1. Sub-world: $W \in V$

  2. Resemblance: if $\varphi^X$ is a formula in prenex normal form, whose matrix is in $L(=,\in)$, and each variable in its prefix must appear as bounded either $\in X$ or $\subseteq X$, then: $$\varphi^V \leftrightarrow \varphi^W $$, is an axiom.

  3. All axioms of "$\sf ZF + \text {CH fails everywhere}"$ relativized to $W$.

What's the consistency strength of $T$?

Let $T$ be a theory formalized in first order logic with equality and membership and the additional primitive constant symbol $W$, with the following axioms:

  1. Extensionality: $\forall z (z \in x \leftrightarrow z \in y) \to x=y$

  2. Class comprehension: if $\phi$ is a formula in which $x$ doesn't occur free, then all closures of: $$\exists x \forall y (y \in x \leftrightarrow \phi \land \exists z (y \in z) ) $$; are axioms.

Define: $x=V \iff \forall y (\exists z (y \in z) \to y \in x)$

  1. Sub-world: $W \in V$

  2. Resemblance: if $\varphi^X$ is a formula in prenex normal form, whose matrix is in $L(=,\in)$, and each variable in its prefix must appear as bounded either $\in X$ or $\subseteq X$, then: $$\varphi^V \leftrightarrow \varphi^W $$, is an axiom.

  3. All axioms of "$\sf ZF + \text {CH fails everywhere}"$ relativized to $W$.

What's the consistency strength of $T$?

Let $T$ be a theory formalized in first order logic with equality and membership and the additional primitive constant symbol $W$, with the following axioms:

  1. Extensionality: $\forall z (z \in x \leftrightarrow z \in y) \to x=y$

  2. Class comprehension: if $\phi$ is a formula in which $x$ doesn't occur free, then all closures of: $$\exists x \forall y (y \in x \leftrightarrow \phi \land \exists z (y \in z) ) $$; are axioms.

    Define: $x=V \iff \forall y (\exists z (y \in z) \to y \in x)$

  3. Sub-world: $W \in V$

  4. Resemblance: if $\varphi^X$ is a formula in prenex normal form, whose matrix is in $L(=,\in)$, and each variable in its prefix must appear as bounded either $\in X$ or $\subseteq X$, then: $$\varphi^V \leftrightarrow \varphi^W $$, is an axiom.

  5. All axioms of "$\sf ZF + \text {CH fails everywhere}"$ relativized to $W$.

What's the consistency strength of $T$?

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Zuhair Al-Johar
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What's the consistency strength of resemblance + global failure of the continuum hypothesis?

Let $T$ be a theory formalized in first order logic with equality and membership and the additional primitive constant symbol $W$, with the following axioms:

  1. Extensionality: $\forall z (z \in x \leftrightarrow z \in y) \to x=y$

  2. Class comprehension: if $\phi$ is a formula in which $x$ doesn't occur free, then all closures of: $$\exists x \forall y (y \in x \leftrightarrow \phi \land \exists z (y \in z) ) $$; are axioms.

Define: $x=V \iff \forall y (\exists z (y \in z) \to y \in x)$

  1. Sub-world: $W \in V$

  2. Resemblance: if $\varphi^X$ is a formula in prenex normal form, whose matrix is in $L(=,\in)$, and each variable in its prefix must appear as bounded either $\in X$ or $\subseteq X$, then: $$\varphi^V \leftrightarrow \varphi^W $$, is an axiom.

  3. All axioms of "$\sf ZF + \text {CH fails everywhere}"$ relativized to $W$.

What's the consistency strength of $T$?