As physical man I spring from other physical men, for I have the same shape as the whole human species. The qualities of the species, accordingly, could be bequeathed to me within the genus. As spiritual man I have my own shape as I have my own biography. I therefore can have obtained this shape from no one but myself. Since I entered the world not with undefined but with defined predispositions; and since the course of my life as it comes to expression is my biography is determined by these predispositions; my work on myself cannot have begun with my birth.  I must, as spiritual man, have existed before my birth. In my forefathers I have certainly not been existent, for they as spiritual human beings are different from me. My biography is not explicable through theirs, On the contrary, I must, as spiritual being, be the repetition of one through whose biography mine can be explained.The physical form which Schiller bore he inherited from his forefathers. But just as little as Schiller’s physical form can have grown out of the earth, so little can his spiritual being have done so. It must be the repetition of another spiritual being through whose biography his will be explainable as his physical human form is explainable through human propagation. In the same way, therefore, that the physical human form is ever again and again a repetition, a reincarnation of the distinctively human species, the spiritual human being must be a reincarnation of the same spiritual human being. For as spiritual human being, each one is in fact his own species.

R. Steiner