Goal:
    x : t  y : t  H : lt x y  H0 : lt y x  H1 : False
  ============================
   (Lt = Gt)


DEBUG:Going to execute:
contradiction
Level 0: Backtrace:

Proof is not complete.
Level 0: Backtrace:

Proof is not complete.
Level 1: Backtrace:

Proof is not complete.
Level 0: Backtrace:

Proof is not complete.
Level 0: Backtrace:

Proof is not complete.