Consider the following premises. forall x_3: ~T(x_3). r or ~T(a_17). T(a_17) <-> r. Can we infer ~r from them?
 From forall x_3: ~T(x_3) we can infer ~T(a_17). From r or ~T(a_17) we can infer T(a_17) -> r. From T(a_17) <-> r we can infer r -> T(a_17). From T(a_17) -> r, r -> T(a_17) we can infer T(a_17) <-> r. Finally, from T(a_17) <-> r, ~T(a_17) we can infer ~r. Therefore, the answer is yes.