- ∀I,K1,L2. G ⊢ K1.ⓘ{I} ⫃![h,a] L2 →
- ∨∨ ∃∃K2. G ⊢ K1 ⫃![h,a] K2 & L2 = K2.ⓘ{I}
- | â\88\83â\88\83K2,W,V. â¦\83G,K1â¦\84 ⊢ ⓝW.V ![h,a] & G ⊢ K1 ⫃![h,a] K2
+ ∀I,K1,L2. G ⊢ K1.ⓘ[I] ⫃![h,a] L2 →
+ ∨∨ ∃∃K2. G ⊢ K1 ⫃![h,a] K2 & L2 = K2.ⓘ[I]
+ | â\88\83â\88\83K2,W,V. â\9dªG,K1â\9d« ⊢ ⓝW.V ![h,a] & G ⊢ K1 ⫃![h,a] K2