From the lecture in GA 216, given on 1922 - 9 - 23 by Rudolf Steiner:
'Since those days humanity has entered upon a quite different phase of evolution, the characteristics of which I have described from many points of view. Since the fifteenth century, mankind has been laid hold of by the intellectualism which now has sovereign sway in all human culture and civilisation, and arose because an older form of speech — the Latin language in its original form, which was still connected with that hearing of rhythm in the Graeco-Roman epoch of which I have spoken — continued far on into the Middle Ages and became entirely intellectual. In many respects the Latin language was responsible for educating man to modern intellectualism. This modern intellectualism, based as it is upon thoughts that are dependent entirely upon the development of the physical body, exposes the whole of mankind to the danger of falling away from the spiritual world. And it can be said with truth that as earlier creeds speak of a Fall into Sin, meaning a Fall more in the moral sense, so, now, we must speak of the danger to which modern humanity is exposed, the danger of a Fall into Intellectualism.
'The kind of thoughts that are universal today, the so-called astute thoughts of modern science to which such great authority is attached — these thoughts are altogether intellectualistic, having their foundation in the human physical body. When the modern man is thinking, he has only the physical body to help him. In earlier periods of earth-existence, thoughts were entirely different in character for they were accompanied by spiritual visions. Spiritual visions were either revealed by the cosmos to man or they welled up from within him. On the waves of these spiritual visions, thoughts were imparted to men from out of the spiritual world. The thoughts revealed themselves to men and such “revealed” thoughts are not accessible to intellectualism. A man who builds up his own thoughts merely according to the logic for which modern humanity strives — such a man's consciousness is bound to the physical body. Not that the thoughts themselves arise out of is the physical body — that, of course, is not the case. But modern man is not conscious of the forces that are working in these thoughts. He does not know what these thoughts are, in their real nature; he is entirely ignorant of the real substance of the thoughts that are instilled into him, even in his school days, by popularised forms of science and literature. He knows them only in the form of mirrored pictures. The physical body acts as the mirror and the human being does not know what is really living in his thoughts; he only knows what the physical body mirrors back to him of these thoughts. If he were really to live within these thoughts, he would be able to perceive pre-earthly existence, and this he cannot do. He is unable to perceive pre-earthly existence because he lives only in mirrored images of thoughts, not in their real substance. The thoughts of modern man are not realities.
'The element of danger for modern evolution lies in the fact that whereas, in truth, the spiritual, the pre-earthly life, is contained in the substance of the thoughts, the human being knows nothing of this; he knows the mirrored pictures. And, as a result, something that is really attuned to the spiritual world falls away. These thoughts are attuned to and have their roots in the spiritual world and are mirrored by the physical body; what they mirror is merely the external world of the senses. In respect of the modern age, therefore, we may speak of a Fall into sin in the realm of intellectualism. The great task of our age is to bring spirituality, the reality of the Spirit, once again into the world of thought and to make man conscious of this. If he wants to live fully in the modern world, a man cannot altogether rid himself of intellectualism, but he must spiritualise his thinking, he must bring spiritual substance into his thoughts.
In the past two weeks I indicated a way to find the substance of thinking. Next week I will indicate another way to reach this form of spiritualisation of thinking.