Let x0 of type ι be given.
Apply unknownprop_85c22e88a806aabda7246f27ac458442bcb94ac25cc9a3616a68cf646d95941d with
x0,
4a7ef...
The subproof is completed by applying unknownprop_eb7b9ba678ea2ffa85e842fbfec0cd6c41d790582268f13f83a490db67168c54 with x0.