We live in our soul-life in the most manifold feelings, perceptions, ideas, concepts, and impulses of will. These all take their course in our soul-life from morning to evening. If we observe man superficially, this soul-life appears to us to be something self-contained, enclosed in itself, and this view is justifiable. Observe how your life flows along with the first thoughts formed in the morning, the first feelings moving through you, the first will-impulses arising. Observe how feeling is linked to feeling, will-impulse to will-impulse, until the evening when the consciousness sinks in sleep. That all looks like a progressing stream.
Observed in a deeper sense, however, it is by no means just a progressing stream, for through our thoughts, feelings and perceptions, we stand in a continual relation — to most people quite unconsciously — to higher worlds. Today let us consider this relation as regards the astral world.
When we have some kind of feeling, when joy or terror flashes through our soul, that, to begin with, is an event in our soul-life, but it is not merely that. If someone can test that clairvoyantly, it will be seen that something goes out of the soul like a current, like a shining current, which goes into the astral world. It does not go in casually, however, and without direction, but it takes its way to a being of the astral world.
Let us suppose a thought arises in our soul; let us say we ponder on the nature of a table. Inasmuch as the thought shimmers through our soul, the clairvoyant can observe how a current proceeds from this thought to a being of the astral world. And so it is for every thought, every concept, every feeling. From the whole stream that flows away before the soul, currents continually go towards the most diverse beings of the astral world.
Source: Rudolf Steiner – GA 107 – The Astral World: Lecture I – Berlin, October 19, 1908