# Re: Tagged formulas

BTW, your suggestion of \E t : t = x works quite well. At first I defined:

Capture(var, Action(_)) == \E t \in S : t = var /\ Action(t) \* S is a constant set known to contain the variable var

and it does the capture/lowering I want.

Then I tried:

Capture(var, Action(_)) == \E t \in {var} : t = var /\ Action(t)

and that works too! I guess that's because the quantification happens outside the priming, and so t is a fresh, bound symbol rather than an _expression_ involving a variable.

Thanks again!