"Starting, then, with these fundamental principles, we will look first at the provision made for physical pain. Men and, I suppose, all living creatures are created with the capacity of suffering. The same nerves of sensation which if excited naturally give rise to pleasure may be excited unnaturally and inflict pain. But why not endow living creatures with nerves of sensation which could experience pleasure, but could not feel pain? Is this possible? Perhaps so, but no man can affirm it with certainty. I do not think that any man can clearly conceive such a thing. To us the capacity of enjoying and that of suffering seem inseparable. But there is no need of insisting upon this point, for the capacity of feeling pain is a most benevolent provision of the Creator for the benefit of living creatures. It is designed to save life and limb. Pain is the sentinel set to guard the outposts of the citadel of life. If there were no pain, men would thrust their hands into flames without knowing it. They would indulge in all manner of destructive excesses, and no sufferings would warn them of danger. They would drink poison, and no pain would bid them make haste to take the antidote. Tear men limb from limb, hew them in pieces with the sword, and no painful sensations would rouse them to self-defence. Without this benevolent provision of pain the race of man could hardly be saved from extinction. How much more would this be true of the animal tribes, which are wholly dependent on instinct for guidance and impulse to action! We accordingly find pain possible in those parts of the body where pain can subserve the purpose of protection; elsewhere no provision is made for pain. Nerves of sensation abound in those parts which require especial care or are especially exposed. The skin is exposed, therefore the skin is well supplied with nerves. The parts beneath the skin are less exposed, and are injured only by first wounding the skin; they are therefore less sensitive. The heart, though so very important, is almost insensible to pain, because the capacity of suffering at that point would confer no protection. The eye is delicate and requires the greatest care, and to secure that needed care the Creator has made it delicately susceptible of pain. The sole of the foot, as its work demanded, was made capable of bearing the roughest usage, and hence the sole of the foot is but little supplied with nerves of sensation. Still farther, when on account of injury any part of the body requires unwonted care, provision is made that the injured part shall become especially sensitive. A bone when well and sound may be cut or sawed almost without pain, but when the bone is injured it becomes inflamed and feels pain most keenly. When a limb for the sake of its own safety ought to be kept quiet, Nature makes it painful to move it. For the benevolent object of preserving life and guarding the well-being of living creatures pain is given.