Consider the following premises. If David were a mechanic, then Mary is an artist. For all x_14, x_14 is an artist if and only if x_14 will drink water. If Mary drinks water, then David is a mechanic. Can we infer the following from them? If we can, name the inference rule being used: The fact that Mary drinks water does not imply that Mary is an artist.
 From the fact that for all x_14, x_14 is an artist if and only if x_14 will drink water we can infer that Mary is an artist if and only if Mary is drinking water via universal instantiation. Finally, from the fact that if Mary drinks water, then David is a mechanic, and that if David were a mechanic, then Mary is an artist we can infer that if Mary drinks water, then Mary is an artist via transitivity, which contradicts that The fact that Mary drinks water does not imply that Mary is an artist. Therefore, the answer is no.