Let x0 of type ι be given.
Apply SNoLt_trichotomy_or_impred with
x0,
1,
False leaving 5 subgoals.
The subproof is completed by applying H0.
The subproof is completed by applying SNo_1.
Assume H4: x0 = 1.
Apply In_irref with
1.
Apply ordinal_SNoLev with
1,
λ x1 x2 . 1 ∈ x1 leaving 2 subgoals.
Apply nat_p_ordinal with
1.
The subproof is completed by applying nat_1.
Apply H4 with
λ x1 x2 . 1 ∈ SNoLev x1.
The subproof is completed by applying H2.