Closely connected with these considerations on the diminution of death, disease, and suffering by improved sanitary arrangements, is the delicate subject of the propagation of hereditary disease.  It is a commonplace that the most important of all the acts of life, is that on which men and women venture most thoughtlessly.  But experience shews, unmistakably, that there are many forms of disease, both mental and bodily, which are transmitted from the parents to the children, and that, consequently, the marriage of a diseased parent, or of a parent with a tendency to disease, will probably be followed by the existence of diseased children.  In a matter of this kind, everything, of course, depends on the amount of the risk incurred, that is to say, on the extent of the evil and the probability of its transmission.  The former of these data is supplied by common observation, the latter by the researches of the pathologist.  It is for the moralist simply to draw attention to the subject, and to insist on the responsibility attaching to a knowledge of it.  The marriages of persons who are very poor, and have no reasonable prospect of bringing up children in health, decency, and comfort, are open to similar considerations but, as in the last case, I must content myself with simply adverting to the responsibility attaching to them, and noting the extent to which that responsibility is usually ignored.  In connexion with this question, it may be added that many of the attempts made by well-meaning people to alleviate poverty and distress have, unfortunately, too often the effect of ultimately aggravating those evils by diverting attention from their real causes.  A not unnatural reluctance to discuss or reflect on matters of this delicate character, combined with the survival of maxims and sentiments derived from an entirely different condition of society, are, doubtless, to a great extent, the reasons of the backward condition of morality on this subject.

The importance, from a social point of view, of the careful education of children with reference to their future position in life has already been considered, but, in connexion with the class of duties I am now treating, I may draw attention to the obligation under which parents lie, in this respect, to their children themselves.  The ancient morality, which was the product of the patriarchal form of society, when the patria potestas was still in vigour, laid peculiar stress on the duties of children to parents, while it almost ignored the reciprocal duties of parents to children.  When the members of a family were seldom separated, and the pressure of population had not yet begun to be felt, this was the natural order of ideas with respect to the parental relation.  But now that the common labour of the household is replaced by competition amongst individuals, and most young men and women have, at an early age, to leave their families and set about earning their own living, or carving out their own career, it is obvious, on