const In : set set prop term iIn = In infix iIn 2000 2000 const SNo : set prop const SNoLt : set set prop term < = SNoLt infix < 2020 2020 term SNoCutP = \x:set.\y:set.(!z:set.z iIn x -> SNo z) & (!z:set.z iIn y -> SNo z) & !z:set.z iIn x -> !w:set.w iIn y -> z < w term Subq = \x:set.\y:set.!z:set.z iIn x -> z iIn y term TransSet = \x:set.!y:set.y iIn x -> Subq y x const SNoLev : set set const SNoR : set set axiom SNoR_I: !x:set.SNo x -> !y:set.SNo y -> SNoLev y iIn SNoLev x -> x < y -> y iIn SNoR x const SNoL : set set axiom SNoL_I: !x:set.SNo x -> !y:set.SNo y -> SNoLev y iIn SNoLev x -> y < x -> y iIn SNoL x axiom SNoLt_tra: !x:set.!y:set.!z:set.SNo x -> SNo y -> SNo z -> x < y -> y < z -> x < z const SNoS_ : set set const add_SNo : set set set term + = add_SNo infix + 2281 2280 const binunion : set set set const Repl : set (set set) set var x:set var y:set var z:set var w:set var u:set hyp !v:set.!x2:set.SNo (v + x2) & (!y2:set.y2 iIn SNoL v -> (y2 + x2) < v + x2) & (!y2:set.y2 iIn SNoR v -> (v + x2) < y2 + x2) & (!y2:set.y2 iIn SNoL x2 -> (v + y2) < v + x2) & (!y2:set.y2 iIn SNoR x2 -> (v + x2) < v + y2) & SNoCutP (binunion (Repl (SNoL v) \y2:set.y2 + x2) (Repl (SNoL x2) (add_SNo v))) (binunion (Repl (SNoR v) \y2:set.y2 + x2) (Repl (SNoR x2) (add_SNo v))) -> !P:prop.(SNo (v + x2) -> (!y2:set.y2 iIn SNoL v -> (y2 + x2) < v + x2) -> (!y2:set.y2 iIn SNoR v -> (v + x2) < y2 + x2) -> (!y2:set.y2 iIn SNoL x2 -> (v + y2) < v + x2) -> (!y2:set.y2 iIn SNoR x2 -> (v + x2) < v + y2) -> P) -> P hyp !v:set.v iIn SNoS_ (SNoLev x) -> SNo (v + y) & (!x2:set.x2 iIn SNoL v -> (x2 + y) < v + y) & (!x2:set.x2 iIn SNoR v -> (v + y) < x2 + y) & (!x2:set.x2 iIn SNoL y -> (v + x2) < v + y) & (!x2:set.x2 iIn SNoR y -> (v + y) < v + x2) & SNoCutP (binunion (Repl (SNoL v) \x2:set.x2 + y) (Repl (SNoL y) (add_SNo v))) (binunion (Repl (SNoR v) \x2:set.x2 + y) (Repl (SNoR y) (add_SNo v))) hyp SNo z hyp SNo (z + y) hyp !v:set.v iIn SNoR z -> (z + y) < v + y hyp SNo w hyp SNo (w + y) hyp !v:set.v iIn SNoL w -> (v + y) < w + y hyp SNo u hyp z < u hyp u < w hyp SNoLev u iIn SNoLev z hyp SNoLev u iIn SNoLev w hyp u iIn SNoS_ (SNoLev x) claim SNo (u + y) -> (z + y) < w + y