Consider the following premises. For all x_8, if x_8 plays tennis, then x_8 is a scientist. For all x_8, if x_8 were a scientist, then x_8 is playing tennis. For all x_8, if x_8 plays tennis, then x_8 is a scientist. Can we infer the following from them? If Susan plays tennis, then Susan is a scientist.
 From the fact that for all x_8, if x_8 were a scientist, then x_8 is playing tennis, and that for all x_8, if x_8 plays tennis, then x_8 is a scientist we can infer that for all x_8, x_8 is a scientist if and only if x_8 will play tennis. From the fact that for all x_8, x_8 is a scientist if and only if x_8 will play tennis we can infer that for all x_8, if x_8 were a scientist, then x_8 is playing tennis. From the fact that for all x_8, if x_8 were a scientist, then x_8 is playing tennis, and that for all x_8, if x_8 plays tennis, then x_8 is a scientist we can infer that for all x_8, x_8 is a scientist if and only if x_8 will play tennis. From the fact that for all x_8, x_8 is a scientist if and only if x_8 will play tennis we can infer that Susan is a scientist if and only if Susan is playing tennis. Finally, from the fact that Susan is a scientist if and only if Susan is playing tennis we can infer that if Susan plays tennis, then Susan is a scientist. Therefore, the answer is yes.