I. Soul and Spirit in the Human Physical Constitution

Let us think, for example, of the blood. Inasmuch as it is mainly fluid, inasmuch as this blood belongs to the fluid organism, we find in the blood the etheric body which permeates it with its forces. But in the blood there is also present what is generally called the warmth-condition. But that ‘organism’ is by no means identical with the organism of the fluid blood as such. If we were to investigate this—it can also be done with physical methods of investigation—we would find in registering the warmth in the different parts of the human organism that the warmth cannot be identified with the fluid or with any other organism.