cases' h with h1 h2
case intro
A : Type
R : A → A → Prop
inhabited_A : Nonempty A
w : X
h : refl_trans_clos RX X.a w ∧ refl_trans_clos RX X.d w
⊢ False
case intro.intro
A : Type
R : A → A → Prop
inhabited_A : Nonempty A
w : X
h1 : refl_trans_clos RX X.a w
h2 : refl_trans_clos RX X.d w
⊢ False