Consider the following premises. If James were a writer, then Joseph is making tea. For all y, y is a writer. For all y, y is a taxi driver. Can we infer the following from them? Joseph is making tea.
 From the fact that for all y, y is a writer, and that for all y, y is a taxi driver we can infer that for all y, y is a writer and y is a taxi driver. From the fact that for all y, y is a writer and y is a taxi driver we can infer that for all y, y is a writer. From the fact that for all y, y is a writer we can infer that James is a writer. Finally, from the fact that if James were a writer, then Joseph is making tea, and that James is a writer we can infer that Joseph is making tea. Therefore, the answer is yes.