We know that the presence of waking consciousness within the nerves-and-senses organism rests upon the fact that the connexion between physical body and etheric body is there the most external of all. But precisely because this is so, the etheric body is dominated very strongly by the forces to which the physical head owes its formation. This, too, is not fundamentally new to us. What can now be added is that, in consequence, the physical brain and the part of the etheric body belonging to it - the etheric brain - assume a function comparable with that of a mirror, the physical organ representing the reflecting mass and the etheric organ its metallic gloss. When, within the head, the etheric body reflects back the impressions received from the astral body, the I becomes aware of them in the form of mental images (the 'ideas' of the onlooker-philosopher). It is also by way of such reflexion that the I first grows aware of itself - but as nothing more than an image among images. Here, therefore, it is itself least active.