This fact, let it be well noted, already determines between mother and child a relation of some duration. The child is altogether unable to live and develop alone. The mother owes it its nourishment; and nature, having herself prepared for the child in the breast of the mother the sources of its subsistence truly indicated thereby that they should be bound to each other by a positive and inevitable tie. It is true the same tie exists also among the families of the animals and their young (at least with mammalia); and we have seen that there exist among them some germs of family. But let us not forget that it takes only a little time for the young of the animal species to reach that degree of strength which enables it to leave its mother without danger. With the human species, on the contrary, it takes a considerable time. Before the first or second year the child is unable to walk; when it walks, it is still unable to walk alone, to find its food, to develop in any way. Imagine a child two, three, five years old, abandoned to himself in a desert island: he would die of hunger. Besides, instinct is much less strong in man than in animals, and much less certain; when an adult, man follows his own reason; in childhood he needs the reason of others. What shall I say of his moral education and intellectual development? The child needs a teacher as well as a nurse. We see that the relations between mother and child must naturally be prolonged far beyond those between animals. The first natural and necessary relations will finally create between these two beings habits of such a character that they will never more separate, even when they can do without each other. At least, this separation will not take place before man is completely man; and although son and daughter may separate from the family to become in their turn heads of families, there will always exist between parents and children certain ties, certain relations, all the closer, as they each follow the laws of nature. In short, children can never be seen, as is the case in the animal species, becoming complete strangers to their father and mother.