Alexander von Humboldt was past fifty before the world of thinking men realized that he had outstripped his brother William--and Alexander would never admit he had. These two men, handsome in face, form and feature: strong in body and poised in mind, with souls athirst to realize and to know--happy men, living long lives of useful effort--surely should be classed as educated persons. And in passing, let us note that all education is preparatory--it is life that gives the finals, not the college. The education of the von Humboldt boys was the Natural Method--the method advocated by Rousseau--the education by play and work so combined that study never becomes irksome nor work repulsive. Rousseau said, "Make a task repugnant and the worker will forever quit it as soon as the pressure that holds him to it is removed." The parents of Alexander and William von Humboldt carefully studied the new plan of education that was at that time being advocated by some of the best professors at Berlin. "A child must have a teacher," said Jean Jacques, "but a professional teacher is apt to become the slave of his profession, and when this occurs he has separated himself from life, and therefore to that degree is unfitted to teach." A school should not be a preparation for life: a school should be life. The Kindergarten Idea, among other things, suggests that a child should never know he is in school. The discipline is kept out of sight, and the youngster finds himself a part of the busy life. He blends in with the others, and works, plays and sings under the wise and loving care of his "other mother," the teacher. He is living, not simply preparing to live. All life should be joyous, spontaneous, natural. The Rousseau Idea, which was modified and refined by Froebel, is the utilization of the propensity to play. Major von Humboldt found a man who was saturated with the true Froebel spirit, although this was before Froebel was born. The man's name was Heinrich Campe. Heinrich was hired to superintend the education of the Humboldt boys. That is to say, he was to become comrade, friend, counselor, fellow-scholar, playmate and teacher. Play needs direction as well as work. Campe played with the boys. They lived with Nature--made lists of all the trees at Tegel, drew sketches of the leaves and fruit, calculated the height of trees, measured them at the base, and cut them down occasionally, first sitting in judgment on the case, and deciding why a certain tree should be removed, thus getting a lesson in scientific forestry. They became acquainted with the bugs, beetles, birds and squirrels. They cared for the horses, cattle and fowls, and best of all they learned to wait on themselves.