The highest type of human being, then, is not merely that which has the most vitality, but also that which can distribute it in due proportion to its various parts, and that which has been permitted to expand naturally in right directions. The extent to which we possess this vitality,--the power we have of assimilating the force stored up in our food, to repair waste and ensure growth,--is largely determined by heredity. True, this fact is in some quarters violently disputed; but not, I think, in quarters deserving of much attention. Distorted people are generally vehement, and resort to bare assertion and flat contradiction when observation, analogy, and rational argument are all with their opponent. It is well, perhaps, when the perverted force-current can steam off so harmlessly instead of working mischief in other channels; just as it is well when excitable political speeches and articles save us from dangerous secret organisations. A young lady once declined to entertain the idea of heredity for a moment, on the ground that, supposing her to be the unfortunate possessor of a grandmother who was a monster of wickedness, she would be expected to prove herself a monster of wickedness likewise. It was in vain for a gentleman present to point out that we usually have more than one grandmother, and that if her other grandmother happened to be an angel of light, she might with equal justice be expected to develop angelic characteristics. She saw her side of the argument, but not his. As a matter of fact, we know so little of the numbers of ancestors from all of whom we may inherit, and we understand so little of the conditions determining the inheritance of given characteristics, that we are not yet in a position to entertain expectations at all. All we know is, that we do not generally get so far as finding grapes on thorns and figs on thistles. The interesting subject of heredity still offers a wide field to the observer. So far, physiological revelation does but prove the truth of the Biblical revelation--that nothing is of ourselves, but that all is of God.