Youth's Search in Nature

Those who have become old in the twentieth century—not in a spiritual but in a conventional sense—will not experience the deep feeling man can have if he is compelled to look upon the human brain as something that has developed (though in a somewhat different direction) in the same way as dung. You must sense these penetrating forces in the human being, however: the brain forms itself like a dung heap. Feel how, in manuring, this dung substantiality is returned to the world-creating forces, so that the spirit can receive it there in a much higher sense than the human spirit can receive what is given to it as material substance from within.