On 23/01/2019 12.29, Sergei Meshveliani wrote: > Maybe the prover could be adopted to the case of > CommutativeRing + the axiom of 0# ≉ 1# ? > > Also, it looks like it fails to prove x - x ≈ 0#, > which can be derived from the Group instance for _+_. I suggest that you study the paper by Grégoire and Mahboubi that I linked to. -- /NAD