Theorem heeq1

Description: Equality law for relations being herditary over a class. (Contributed by RP, 27-Mar-2020)

	Ref	Expression
Assertion	heeq1	$$⊢R=S\to \left(RhereditaryA\leftrightarrow ShereditaryA\right)$$

Proof

Step	Hyp	Ref	Expression
1		eqid	$$⊢A=A$$
2		heeq12	$$⊢\left(R=S\wedge A=A\right)\to \left(RhereditaryA\leftrightarrow ShereditaryA\right)$$
3	1 2	mpan2	$$⊢R=S\to \left(RhereditaryA\leftrightarrow ShereditaryA\right)$$