bi.bldald

Theorem.

Arguments:

x (sv), phi (pr), psi (pr), chi (pr),

Hypotheses:

(phito(psileftrightarrowchi))
(x bound in phi)

Assertions:

(phito(forallxpsileftrightarrowforallxchi))

Proof:

Hyp Ref Line Expr
Hypo1(phito(psileftrightarrowchi))
2(x bound in phi)
1, 2imgen>i3(phitoforallx(psileftrightarrowchi))
eqt-∀4(forallx(psileftrightarrowchi)to(forallxpsileftrightarrowforallxchi))
3, 4syl5(phito(forallxpsileftrightarrowforallxchi))