Let x0 of type ι be given.
Let x1 of type ι be given.
Apply minus_SNo_minus_CSNo with
x1,
λ x2 x3 . x0 = x2 ⟶ and (x0 = 0) (x1 = 0) leaving 2 subgoals.
Apply omega_SNo with
x1.
The subproof is completed by applying H1.
Apply nonpos_nonneg_0 with
x0,
x1 leaving 2 subgoals.
The subproof is completed by applying H0.
The subproof is completed by applying H1.