Consider the following premises. For all x_6, x_6 is a writer. For all x_6, if x_6 were a scientist, then x_6 is reading a book. There is at least one x_6 for which x_6 is a writer if and only if x_6 will read a book. Can we infer the following from them? For all x_6, x_6 will not read a book.
 From the fact that for all x_6, x_6 is a writer we can infer that for all x_6, x_6 is a writer or x_6 is a scientist. From the fact that there is at least one x_6 for which x_6 is a writer if and only if x_6 will read a book we can infer that there is at least one x_6 for which if x_6 were a writer, then x_6 is reading a book. Finally, from the fact that there is at least one x_6 for which if x_6 were a writer, then x_6 is reading a book, that for all x_6, if x_6 were a scientist, then x_6 is reading a book, and that for all x_6, x_6 is a writer or x_6 is a scientist we can infer that there is at least one x_6 for which x_6 will read a book, which contradicts that For all x_6, x_6 will not read a book. Therefore, the answer is no.