P(H0), rrP(r, r0)(H1), H1 ⊥ H0 ⊦ ∃ r0, r1. ((rrP(r0, r1) * P))(H1 ∪ H0)
Used simplifier rules: ex2: ⊦ (_∃ rrP)(H) ↔ (∃ r0, r1. rrP(r0, r1)(H));