| eqex(st1, st0, r), eqex(st0, st, r), eqex(st0, st1, r), eqex(st, st0, r) ⊦ st -- r = st1 -- r |
⊦ eqex(st, st0, r) ↔ st -- r = st0 -- r
eqex(st1, st0, r), eqex(st0, st, r), eqex(st0, st1, r), st -- r = st0 -- r ⊦ st -- r = st1 -- r
[[CONCRETESIMPRULES : ()], [EXTRATERMS : (r, st0, st)]]