I. Haeckel and His Opponents

No scientific consideration would be able to rob man of the conviction that perceptible phenomena are guided by beings outside the world, if he could find within his own consciousness anything that pointed to such beings. What could anatomy and physiology accomplish with their declaration that soul-activities are functions of the brain, if observation of these activities yielded anything which could be regarded as a higher ground for an explanation? If the philosopher were able to show that a universal world-reason manifests itself in human reason, then all scientific results would be powerless to refute such knowledge.