In Words and Rules, Pinker manages to condense and tie together an unbelievable amount of research. Reading this book carefully (i.e. really absorbing the densely packed information) and looking up some of its references is probably equivalent to a good undergraduate degree in linguistics.
Pinker has a knack for teasing apart all the different threads that make up a hugely complex subject, exploring each one with arguments and data from different academic currents, and then tying them up again so the reader can form a much better picture of the whole. And that's exactly what he does in this flawlessly well-written book.