Man cannot achieve progress by keeping as it were to the middle line, although there are many who realise the uselessness of adopting a one-sided standpoint. Admittedly, we come across idealists, materialists and other ‘-ists’ who swear by their own standpoint, but truly great individuals such as Goethe do no such thing. They try to grasp material conditions by means of material thinking. When men of less eminence imagine that they have understood this, they say: truth lies in the middle, between two different standpoints.
But that would be the same as if someone in practical life wanted to sit between two chairs! The truth cannot be found by a one-sided adoption of this or that standpoint but by applying the modes of knowledge appropriate either for materialism or idealism, The world does not progress by undeviating adherence to a middle course: a middle course is appropriate when the opposing sides are also present and are recognised as forces.
Source: Rudolf Steiner – GA 141 – Between Death and Rebirth: Lecture 7 – Berlin, 14th January 1913
Translated by E. H. Goddard & D. S. Osmond