theorem Th19: :: FACIRC_1:19

for S being non empty non void Circuit-like ManySortedSign
for A being non-empty Circuit of S
for s being State of A
for g being Gate of S st ( for x being set st x in rng (the_arity_of g) holds
s is_stable_at x ) holds
Following s is_stable_at the_result_sort_of g