For Paley, a watch is purposeful and thus must have been created by a being with a purpose. A watch needs a watchmaker, just as a world needs a world-maker—God. Yet both Wallace and Paley...

In 1867, George Campbell, Duke of Argyll, had published The Reign of Law, a book that Darwin found deeply annoying. A supporter of Richard Owen, Campbell argued that while evolution (or “Development”) might be observable...