I ask you to consider, first, the intellectual fallacy which underlies this method of research. It is a twofold fallacy, resulting from the differences of organization in different classes of living creatures, and from the fact that when any organ is injured, it is a process of destruction or death--not life--that is exhibited. There is an ineradicable difference of physical structure between Man and every species of lower animal. Nowhere is there identity of structure or of function. Resemblance or parallelism often exists, but identity never. Take the dog, for instance, whose attachment to Man furnishes us with the widest opportunities of observation. In no single function of its body is the action of the function the same as in Man. All the processes of digestion, including its large group of connected organs, differ from those of the human being. Observe carefully the processes of healthy living animals. You will find that their senses act in a different way to ours--a way which is often quite unknown to us, we possessing no power even comparable with many of their powers. Their relations to nature differ in many ways from our relations. It is true that they eat and sleep and dream; that they possess intellectual and moral powers, and are susceptible of education. They exhibit a rough rudimentary sketch of our higher spiritual powers, and are related to us in many ways. But the differences are so great, their whole attitude towards external life is so different, that they may be truly said to live in a different world from ours. So that in no possible instance can we draw a positive conclusion respecting the lower animal nature, that can be transferred as reliable information to guide us in relation to the action of the human organs and functions, either in health or disease. This misleading difference is true not only in relation to the spontaneous working of functions, but it is also true in respect to the actions of poisons, of drugs, and the artificial production of diseases. Animals can be rendered scrofulous, diabetic, syphilitic, leprous, by forcing the poison of diseases into their bodies. Morbid action, atrophy, slow death, can be produced by removing portions of their organs; but no deductions drawn from these artificial conditions can be transferred to man in order to cure human disease or restore lost function. The scrofula, diabetes, syphilis, or rabies, takes on a different form when the lower animal has been artificially poisoned by these diseases. In not a single instance known to science has the cure of any human disease resulted necessarily from this fallacious method of research.