Theorem moimiOLD

Description: Obsolete version of moimi as of 9-May-2023. The at-most-one quantifier reverses implication. (Contributed by NM, 15-Feb-2006) (Proof modification is discouraged.) (New usage is discouraged.)

	Ref	Expression
Hypothesis	moimiOLD.1	$$⊢\phi \to \psi$$
Assertion	moimiOLD	$$⊢{\exists }^{*}x\psi \to {\exists }^{*}x\phi$$

Proof

Step	Hyp	Ref	Expression
1		moimiOLD.1	$$⊢\phi \to \psi$$
2		moim	$$⊢\forall x\left(\phi \to \psi \right)\to \left({\exists }^{*}x\psi \to {\exists }^{*}x\phi \right)$$
3	2 1	mpg	$$⊢{\exists }^{*}x\psi \to {\exists }^{*}x\phi$$