1 September 1921, Stuttgart
At the same time that the Philosophy of Freedom appeared there also came out Haeckel's Monism as a Link between Religion and Science. Rudolf Steiner saw that here was a sure ground from whence the investigator can penetrate into the spiritual worlds. All investigation must be formed on monistic lines. But what is to be understood by monism? How can nature and spirit be grasped in a monistic way? Upon these questions Haeckel, the great experimentalist, was quite elementary. From Goethe we can get a better answer. He shows that nature must be understood poetically, for art is the revealer of nature's secrets. The world is not fitted to surrender its nature to merely logical thinking.
It was in his investigation of the plant world that Goethe was especially great. One can understand why this was so if one notes that Goethe, in a certain sense, was on the road to becoming a sculptor. The leaning towards sculpture, existing in the depths of his nature, made him a modeller in his working out of his Metamorphosis of the Plant. What is plastic in plant formation he grasped through this unexpressed talent for sculpture. One cannot look plastically upon animal and human form in the same way that one can regard the plant world. This comes to expression in the fact that we are repelled by plastic reproductions of plants, which is not the case in regard to human and animal forms. The plant is really a work of art in Nature, so that one is not able to transcend its natural form, and on this account the plant does not allow itself to be reproduced in art.
In Goethe, however, there lived a restrained, hidden plastic faculty which did not culminate in him in sculpture, but which appears in his dramas. He could not give it shape in clay, but in nature he finds something which satisfies his instinct for what is plastic and this is the world of plants. In inorganic nature we measure, count and weigh, and this breaks up form. Goethe saw the plant as a unity. He saw this unity as that which Anthroposophy calls the plant's etheric body. We find this etheric also in men and animals and the sculptor aims at bringing it to expression in the sculptured form. Yet someone who, like Goethe, holds back his talent in regard to the plastic art, can through this restraint discover certain secrets in nature. In this way Goethe arrived at his doctrine of the metamorphosis of plants.
In a similar, if in a more naive, way did Haeckel look upon the animal world. In him also existed ‘imaginative thinking,’ and this he applied to animals. He spoke of the ‘soul’ in the animal world, and by this he meant that whoever during many years had watched the lower animals must perceive this ‘germ soul.’ There is consequently a certain relationship between the outlook of Haeckel upon animals (soul) and the outlook of Goethe upon plants (form).
Now it is particularly interesting to notice that Haeckel also, in a dilettante way, was something of a painter, and this proclivity gave him an understanding for what the animal world conjures to the surface as colour. He has produced the book Nature's Art Forms. He lived with colour as Goethe lived with form. What belongs to animals has a far more intimate connection with colour than what is expressed in form in the plant world. The colour of flowers belongs to what is outer, to sun and air, but with animals colour is bound up with what is of the soul, of the instincts, and so on. In Anthroposophy this is named the ‘astral body.’ Haeckel's understanding of the animal kingdom is thus connected with his latent talent for painting. He did not conduct his studies in any outward way but, like Goethe, from a latent feeling for art. Nietzsche could not press on to all this for lack of nature knowledge, and so he could not have the right relation to his epoch.
Anthroposophy maintains a due regard to this nature knowledge, and, when anything is spoken from out the springs of Spiritual Science, it must always be referred to that other fount. Agnostic methods of thinking must be put aside in all research, but what Rudolf Steiner induces is a closer agreement with Haeckel in so far as he was the first to create a philosophy adapted to our period. What Goethe accomplished for botany and Haeckel for zoology, Rudolf Steiner achieves for anthropology.