Paley’s account of the function of the annular ligament at the ankle is correct, and strikingly put. A similar ligament occurs at the wrist, and navvies who have hard muscular work to do in digging and shovelling are wont to reinforce this ligament and to keep it from rupture by a leather strap round the wrist. The strap performs exactly the same function as the ligament, and from Paley’s point of view one is as artificial, as much a ‘contrivance,’ as the other. But his point of view is wrong. He conceives the Creator as having at his disposal fully formed elements or materials—sinews, bones, ligaments, and the like—and assembling them into a working mechanism. In fact, however, none of these things is now what it was originally—time, as Plato says, has changed its “name and shape.” The annular ligaments are recognized by modern anatomists as having originated in special thickenings of the fascial sheaths of the adjoining muscles of the wrist and ankle. They had a function which was not originally connected with keeping down the long tendons that run along the interior angle of the leg and foot. Contractility, as biologists tell us, is a fundamental property of living protoplasm; and it is easy to imagine that, at the very beginning of the formation of muscular structure and bone articulation, two lines of contractile force might cross each other and thus permit the gradual evolution of the present arrangement, nature continually visiting with disability and extinction those individuals in whom the resisting power of the muscles which were eventually to form the annular ligament was unduly feeble, and giving a better chance of life, and of the propagation of their kind, to those in whom it was strong. The instance, in fact, is one of those in which the explanation of development by natural selection is most obvious and plausible. In his second paragraph Paley touches on the theory of “appetency,” the supposed tendency of natural structure to alter and adapt itself on the lines indicated by the actual exercise of function, and in consequence of that exercise. This is practically the theory since identified with the name of Lamarck. Paley scarcely does it justice, for no Lamarckian would suggest that a muscle could, in the course of its exercise, develop the ligament whose function is to restrain it. The ligament would be developed by its own exercise. But as Lamarckism will be discussed later on, the issue as between these rival theories need not be debated here.