We shall not set up demands nor programmes, but simply describe the child-nature. (...) Vague and general phrases — 'the harmonious development of all the powers and talents in the child,' and so forth — cannot provide the basis for a genuine art of education. Such an art of education can only be built up on a real knowledge of the human being. Not that these phrases are incorrect, but that at bottom they are as useless as it would be to say of a machine that all its parts must be brought harmoniously into action. To work a machine you must approach it, not with phrases and truisms, but with real and detailed knowledge.

The Education of the Child in the Light of Anthroposophy (GA 34), an essay of 1909.