Anyone whose senses are opened to the astral world will at first be bewildered, because there is really nothing in the physical world with which he can compare it. The astral world has a whole range of characteristics of its own and he has to learn many new things. One of the most perplexing aspects of this world is that all things appear reversed, in a sort of mirror-reflection, and he has to get used to seeing everything in a new way. For instance, he has to learn to read numbers backwards. We are accustomed to read the figures 3, 4, 5, as 345 but in the astral world we have to read them backwards as 543. Everything appears as its mirror-reflection, and it is essential to be aware of this.
The same law applies also to higher things — in the field of morality, for instance. People do not at first understand this. It may happen that they see themselves surrounded by black, malignant forms which threaten and terrify them — this happens with very many people and they mostly have no idea what it signifies. The fact is that these figures are their own impulses, desires and passions, which live in what we call the astral body. Ordinary people do not see their own passions, but these may sometimes become visible as a result of processes active in the brain and soul, and then they appear as mirror-images. You see the mirror-images of your desires in the same way as when looking into a mirror you see reflected images of the objects around you. Everything that comes out of you seems to be going into you. Further, time and events move backwards. In the physical world you see first the hen and then the egg. In the astral world you see the egg and then the hen that laid it. Time in the astral moves backwards: you see first the effect and then the cause. This explains how prophecy is possible — if it were not for this reversal of the time-sequence it would be impossible to foresee events.
Source: Rudolf Steiner – GA 95 – At the Gates of Spiritual Science: LECTURE TWO: THE THREE WORLDS – Stuttgart, 23rd August 1906
Translated by E.H. Goddard & Charles Davy
Previously posted on March 19, 2019