Apply In_ind with
λ x0 . ∀ x1 . ordinal x0 ⟶ ordinal x1 ⟶ or (or (prim1 x0 x1) (x0 = x1)) (prim1 x1 x0).
Let x0 of type ι be given.
Apply In_ind with
λ x1 . ordinal x0 ⟶ ordinal x1 ⟶ or (or (prim1 x0 x1) (x0 = x1)) (prim1 x1 x0).
Let x1 of type ι be given.
Apply xm with
prim1 x0 x1,
or (or (prim1 x0 x1) (x0 = x1)) (prim1 x1 x0) leaving 2 subgoals.
Apply or3I1 with
prim1 x0 x1,
x0 = x1,
prim1 x1 x0.
The subproof is completed by applying H4.
Apply xm with
prim1 x1 x0,
or (or (prim1 x0 x1) (x0 = x1)) (prim1 x1 x0) leaving 2 subgoals.
Apply or3I3 with
prim1 x0 x1,
x0 = x1,
prim1 x1 x0.
The subproof is completed by applying H5.
Apply or3I2 with
prim1 x0 x1,
x0 = x1,
prim1 x1 x0.
Apply set_ext with
x0,
x1 leaving 2 subgoals.
Let x2 of type ι be given.
Apply ordinal_Hered with
x0,
x2 leaving 2 subgoals.
The subproof is completed by applying H2.
The subproof is completed by applying H6.
Apply or3E with
prim1 x2 x1,
x2 = x1,
prim1 x1 x2,
prim1 x2 x1 leaving 4 subgoals.
Apply H0 with
x2,
x1 leaving 3 subgoals.
The subproof is completed by applying H6.
The subproof is completed by applying L7.
The subproof is completed by applying H3.
The subproof is completed by applying H8.
Assume H8: x2 = x1.
Apply FalseE with
prim1 x2 x1.
Apply H5.
Apply H8 with
λ x3 x4 . prim1 x3 x0.
The subproof is completed by applying H6.
Apply FalseE with
prim1 x2 x1.
Apply H5.
Apply ordinal_TransSet with
x0,
x2,
x1 leaving 3 subgoals.
The subproof is completed by applying H2.
The subproof is completed by applying H6.
The subproof is completed by applying H8.
Let x2 of type ι be given.
Apply ordinal_Hered with
x1,
x2 leaving 2 subgoals.
The subproof is completed by applying H3.
The subproof is completed by applying H6.
Apply or3E with
prim1 x0 x2,
x0 = x2,
prim1 x2 x0,
prim1 x2 x0 leaving 4 subgoals.
Apply H1 with
x2 leaving 3 subgoals.
The subproof is completed by applying H6.
The subproof is completed by applying H2.
The subproof is completed by applying L7.
Apply FalseE with
prim1 x2 x0.
Apply H4.
Apply ordinal_TransSet with
x1,
x2,
x0 leaving 3 subgoals.
The subproof is completed by applying H3.
The subproof is completed by applying H6.
The subproof is completed by applying H8.
Assume H8: x0 = x2.
Apply FalseE with
prim1 x2 x0.
Apply H4.
Apply H8 with
λ x3 x4 . prim1 x4 x1.
The subproof is completed by applying H6.
The subproof is completed by applying H8.