Consider the following premises. James is reading a book if and only if it is raining. It is not raining. Richard is fast if and only if James is reading a book. Can we infer the following from them? If we can, name the inference rule being used: Richard is fast.
 From the fact that James is reading a book if and only if it is raining, and that it is not raining we can infer that James is not reading a book via biconditional elimination. Finally, from the fact that Richard is fast if and only if James is reading a book, and that James is not reading a book we can infer that Richard is not fast via biconditional elimination, which contradicts that Richard is fast. Therefore, the answer is no.