In the widest treatment of the maternal instinct it will not suffice to narrow our attention to the function of human motherhood, or to take up our study of the conditions relating to the mother and the child as we find them amongst us to-day. Were I to do this and to attempt at once to bring forward my own views, with the reforms that I wish for in this matter, my work would be as a building without a firm foundation, more or less uncertain, and for this reason valueless.

To get a proper grip of all that is here concerned we must understand that the maternal instinct is the deepest and strongest instinct in woman. It is in the emotions and actions either directly arising from or connected with motherhood that we find the real difference between the sexes. In its essence the parental instinct belongs to woman alone. The male may be infected with its energy—we witness this among birds, as well as in humbler animals, where the duties of caring for offspring are shared and, in some cases, carried out by the male alone; but man possesses, as yet, its faint analogy only. It is the most primary of all women’s qualities.[9]

Now, why is this? Why is woman’s being so much more strongly infected with motherhood than the man’s with fatherhood?

It is a question not so readily to be answered as it might appear. If we find the explanation in the intimate connection between the mother and the child we have not, I think, exhausted the matter. We must not forget that other questions remain behind unanswered, all centring round the one question to which an adequate answer is so difficult to find: How has this arisen? The fact has to be explained that the sharp separation in the parental impulse and the parental duties, so strong amongst us, has not always existed; that there are many examples in the history of life which show an exactly opposite condition.

To find the clue it will thus be necessary to turn our attention to the earlier stages of life where, in particular among insects, reptiles, fishes, and birds, we find the widest possible range of difference in the expression of the parental instinct and the most varied relations existing between parents and offspring. Here indeed, among these pre-human parents, we can study the maternal instinct in the making. There are many new and strange facts for us to learn.

I know well the dangers of such an inquiry. To many, who will allow its interest, it will yet appear as being profitless. There is perhaps some justification for this view. Certainly any attempt to establish the conditions of human motherhood from examples in natural history must be far from conclusive. All comparisons of our own habits and impulses with their earlier expression as we see them in the animals are somewhat unsatisfactory. The lines on which human motherhood has developed and the conditions which have so largely helped to shape its expression, differ vastly from many of the other needs and circumstances which govern the activities of parents in the lower forms of life. Chief among these differences is the more complex character of the human brain, which is correlated with the far greater length of time that the human infant is dependent on its mother.

Yet, allowing for all this difference, I believe that there is much for us to learn from the life-histories of these pre-human parents. At least we find wonderful agreement prevailing between the conduct which we think reason dictates to us and that which we hold instinct dictates to the animals. And the question will be forced upon us: How far back in the record of life did the fierce mother-instinct exist? We shall find many unheeded examples, alike of its operation and of its failure to operate, which, if we consider them, in the light they may possibly cast forward on our own problems, will not fail to bring us to some unexpected conclusions. Life is full of surprises, and this matter of the care of the young affords not the least of them. Nowhere are the links between the present and the past more fascinatingly represented.

I am far indeed from being able to explain many facts I have come to know. I have been puzzled often, and the suggestions I offer I know may be wrong. The early stages in the growth of parental care, even among the animals whose habits are known to us, are often enshrouded in mystery, baffling the penetration of the most patient and careful inquirers. Nevertheless, during recent years a host of facts have been gathered together which throw much new light not only on the theme of pre-human parenthood, but also on the probable action of the parental instinct as it has slowly developed through the ages.

But apart from such more speculative considerations there are yet other aspects to be considered, such as the effect of the environment, the conditions of the home, and the type of union between the male and the female, all of which have their influence on the duration and kind of care shown by animal parents to their offspring. Some explanation must be sought for the almost bewildering diversity which we find in this relationship; for while the young of some animals (and often among low types where least we should expect it) are jealously guarded and cared for by at least one of the parents, in others there is no trace of such sacrifice and solicitude, and the young are thrown on to the world, orphaned before they are born, and left to live or die as chance decrees. Why is this? Why is the parental instinct so actively strong in some cases, so absent in others? Can we, indeed, hope to find the answer? If we can do this, we shall learn much to surprise and also to instruct us.