In all the so-called mental diseases, the primary cause lies in the organic system, although this is often very hard to detect. And for just this reason it is sad to note how ineffective so-called mental and spiritual treatment often proves; so that there is more chance of obtaining a cure in organic diseases through treatment of the mind and spirit, than in the diseases termed “mental.” Yes, we must learn to treat mental diseases with physical remedies. That is a matter of major importance, and the second field in which external medicine will have to let its path be sought and found: the path leading to spiritual science.
Source: Rudolf Steiner – GA 312 – Spiritual Science and Medicine: Lecture XIII – Dornach, 2nd April, 1920
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