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 SNoS_ : set set axiom SNoS_I2: !x:set.!y:set.SNo x -> SNo y -> SNoLev x iIn SNoLev y -> x iIn SNoS_ (SNoLev y) const add_SNo : set set set term + = add_SNo infix + 2281 2280 const SNoL : set set const SNoR : set set const binunion : set set set const Repl : set (set set) set lemma !x:set.!y:set.!z:set.!w:set.!u:set.(!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) -> SNo y -> (!v:set.v iIn SNoS_ (SNoLev y) -> SNo (x + v) & (!x2:set.x2 iIn SNoL x -> (x2 + v) < x + v) & (!x2:set.x2 iIn SNoR x -> (x + v) < x2 + v) & (!x2:set.x2 iIn SNoL v -> (x + x2) < x + v) & (!x2:set.x2 iIn SNoR v -> (x + v) < x + x2) & SNoCutP (binunion (Repl (SNoL x) \x2:set.x2 + v) (Repl (SNoL v) (add_SNo x))) (binunion (Repl (SNoR x) \x2:set.x2 + v) (Repl (SNoR v) (add_SNo x)))) -> SNo z -> SNo (x + z) -> (!v:set.v iIn SNoR z -> (x + z) < x + v) -> SNo w -> SNo (x + w) -> (!v:set.v iIn SNoL w -> (x + v) < x + w) -> SNo u -> z < u -> u < w -> SNoLev u iIn SNoLev z -> SNoLev u iIn SNoLev w -> SNoLev u iIn SNoLev y -> u iIn SNoS_ (SNoLev y) -> (x + z) < x + w 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 SNo y hyp !v:set.v iIn SNoS_ (SNoLev y) -> SNo (x + v) & (!x2:set.x2 iIn SNoL x -> (x2 + v) < x + v) & (!x2:set.x2 iIn SNoR x -> (x + v) < x2 + v) & (!x2:set.x2 iIn SNoL v -> (x + x2) < x + v) & (!x2:set.x2 iIn SNoR v -> (x + v) < x + x2) & SNoCutP (binunion (Repl (SNoL x) \x2:set.x2 + v) (Repl (SNoL v) (add_SNo x))) (binunion (Repl (SNoR x) \x2:set.x2 + v) (Repl (SNoR v) (add_SNo x))) hyp TransSet (SNoLev y) hyp SNo z hyp SNo (x + z) hyp !v:set.v iIn SNoR z -> (x + z) < x + v hyp SNo w hyp SNoLev w iIn SNoLev y hyp SNo (x + w) hyp !v:set.v iIn SNoL w -> (x + v) < x + w hyp SNo u hyp z < u hyp u < w hyp SNoLev u iIn SNoLev z hyp SNoLev u iIn SNoLev w claim SNoLev u iIn SNoLev y -> (x + z) < x + w