Rudolf Steiner is one of the well known authors of the late pre-modern occult world. A student of theosophy who became the head of anthroposophy, his works were profuse, but among all of these, "Occult Significance of Blood" stands out as perhaps the best. Speaking of interbreeding and the spiritual result, the race question (then in vogue in philosophical circles) and the biological concept of blood in general, Steiner's work is highly indicative of its date of origin and symbolizes the confusion of the 1910s.