Let x0 of type ι be given.
Let x1 of type ι be given.
Apply minus_SNo_Le_swap with
1,
x0,
x1 leaving 4 subgoals.
The subproof is completed by applying SNo_1.
The subproof is completed by applying H0.
The subproof is completed by applying H1.
The subproof is completed by applying H2.