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Elliot Glazer
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Accepting the convention that it is a logical axiom that the universe is nonempty, the answer is yes. We will formalize the transitive closure axiom schema (TC) as follows: for any definable (with parameters) binary relation $R,$ if for all $x,$ $\{y: y R x\}$ is a set, then for all $x,$ there is a set $S$ such that $x \in S$ and $S$ is closed downwards under $R.$ Of course, this can only be weaker than asserting the existence of a minimum such $S.$

For efficiency, we will prove Pairing, Union, Infinity, and Replacement from Extensionality, Separation, and your transitive closure schema.

Pairing: We first note that $\emptyset$ exists by applying separation to an arbitrary set. Next, for all $x,$ $\{x\}$ exists by applying TC to $x$ and the empty relation. Finally, for all $x, y,$ we get $\{x,y\}$ by applying TC to $x$ and the relation defined by $a R b$ iff $a = x$ and $b=y.$

Union: Fix a set $S.$ By Separation and Russell's paradox, there is $x \not \in S.$ Define $R$ by $a R b$ iff $a = x$ and $b = S$ or $a \in S$ and $b \in a.$ Then we get $\bigcup S$ by applying TC to $x$ and $R.$

Infinity: Define a relation $R$ by $a R b$ iff $a$ and $b$ are natural numbers and $a=b+1.$ Then $\omega$ exists by applying TC to $\emptyset$ and $R.$

Replacement: Fix a set $S$ and a definable function $F.$ Fix $x \not \in S.$ Define $R$ by $a R b$ iff $a=x$ and $b=S$ or $a \in S$ and $b = F(a).$ Then we get $F"S$ by applying TC to $x$ and $R.$

Elliot Glazer
  • 4.3k
  • 2
  • 24
  • 40