The first year of life was formerly regarded as lying outside the sphere of education. At least until the infant could speak, if not longer, it was left to the entirely unchecked care of mothers and nurses, who were supposed to know by instinct what was good for the child. As a matter of fact, they did not know. An enormous proportion of children died during the first year, and of the remainder many were already ruined in health. By bad handling, the foundations had been laid for disastrous habits of mind. All this has only recently been realized. The invasion of the nursery by science is often resented, because it disturbs the sentimental picture of mother and child. But sentimentality and love cannot coexist; the parent who loves his or her child will wish it to live, even if it should be necessary to employ intelligence for the purpose. Accordingly we find this sentimentality strongest in childless people and in people who, like Rousseau, are willing to leave their children to the Foundling Hospital. Most educated parents are eager to know what science has to say, and uneducated parents, also, learn from maternity centres. The result is shown in the remarkable diminution of infant mortality. There is reason to think that, with adequate care and skill, very few children would die in infancy. Not only would few die, but the survivors would be healthier in mind and body. Questions of physical health, strictly speaking, lie outside the scope of this book, and must be left to medical practitioners. I shall touch on them only where they have psychological importance. But physical and mental are scarcely distinguishable in the first year of life. Moreover the educator in later years may find himself handicapped by purely physiological mistakes in handling the infant. We cannot therefore altogether avoid trespassing upon ground which does not of right belong to us.