A fit of passion in a nursing mother has destroyed her infant; the industrious cultivator seeing his field of strawberries, the products of his toil, carried off by thieves, has fallen dead in his vain efforts to stop the cruel depredation. But such instances are world-wide, and corroborated by everyone’s experience. They prove that, although the forces of mechanics, physics, and chemistry are employed in the animal economy, there are also powers far beyond these limited forces, which must be studied also in biological research, if we are to learn how these physical may be overridden by mental forces. Without such correlation of knowledge we fail to realize the unity of Nature, and cannot attain to true science or proved knowledge. It is thus seen that, as already stated, in useful scientific investigation the object to be attained, the method to be employed, and the application to be made of the knowledge searched for, must all be considered in determining the distinction between genuine science and simple unguided intellectual activity or curiosity. It is necessary to emphasize the fact, because this vital distinction is often overlooked in the claim now made for the grand term ‘science.’ In defining the meaning and scope of science as pursued by rational beings, it must be recognised as a fundamental principle, which cannot be too often dwelt upon, that what we can do, is not a measure of what we ought to do. Thus, when Stanley attempted to excuse the infamous action of his naturalist, Jameson,[18] by saying that he was a real good fellow, but ‘his science misled him,’ he degraded the term ‘science’ by applying it to an act of morbid curiosity. Again, when the Russian nobleman purchased a child and condemned it to be brought up with a deaf and dumb nurse, under the unnatural condition of deprivation of all social relations, his action was not scientific, but a gratification of inhuman curiosity. It is within our power apparently to drown an animal, human or brute, and recover it to life again and again, but we gain no scientific knowledge by so doing. We torture the creature and violate our natural instincts, but we acquire no practical benefit to human welfare; on the contrary, we endanger the mental integrity of the experimenter.