It is not within the scope of this work to enter upon an inquiry into the scientific evidence of the existence of the soul or advance any argument whatever in support of that doctrine, but I assume the existence of an immortal soul to be a fact. What I will endeavor to explain is when and where this mystic union of the soul with the body takes place? Here the speculations of the medical philosophers have been contradictory, on account of attributing to the fetus different kinds of life, that is, an organic or vegetating existence attached to the mother’s womb, and as such not possessed of sentient principle, until the real or spiritual life imbues the fetus, when it becomes a living soul. Hippocrates, the most famous physician of antiquity, who, even in the light of the nineteenth century, looms up as one of the most brilliant intellects that the world ever had, lent the weight of his judgment to this very unreasonable doctrine. He supposed that animation occurred from thirty to forty-two days after conception. The Stoics went still further and maintained that there was no vitality until after birth and the establishment of respiration. The Academicians were of the opinion, that life was imparted to the fetus during the period in which the mother carried it in the womb, but they could not agree on the time when it began. Even the Roman Church, which, in the main, is right on this question, speaks of _animate_ and _inanimate_ fetuses. When it is remembered that there was no scientific physiology upon which the ancients based their opinions, it is not at all surprising that, in the light of modern research, they are shown to be all wrong. There is no time during the child’s sojourn in the mother’s womb that life is less active than at another, and any opinion to the contrary is manifestly absurd and unscientific. I appreciate the distinction between _physical life_, or vital activity, and spiritual life, but the one must necessarily be in the other. A central fountain of physical force is consistent with scientific deductions, and physicists are inclined to admit such a source. Many of the phenomena of the material world are explained upon this hypothesis. The sun is supposed to be that central fountain of physical force which inspires activity in matter on this planet. Matter in itself is inert and motionless; the globe we inhabit has no energy in itself which could keep it in motion, but the forces playing on and around it impart to it its motive power.