But as soon as we penetrate into the psycho-spiritual world such elucidations become less easy. In the world of sense, facts are not altered by human delusions about them; it is therefore possible to correct a delusion by unprejudiced observation of facts. But in the supersensible world this is not immediately possible. If we desire to study a supersensible occurrence and approach it with the wrong judgment, we then carry that wrong judgment over into the thing itself, and it becomes so interwoven with the thing, that the two cannot be easily distinguished. The error then is not in the person and the correct fact external to him, but the error will have become a component part of the external fact. It cannot therefore be cleared up simply by unprejudiced observation of the fact. This is enough to indicate an extremely fertile source of illusion and deception for one who would venture to approach the supersensible world without adequate preparation. As the occult student has now acquired the faculty to exclude those illusions originating from the coloring of the supersensible world-phenomena with his own being, so must he now acquire the faculty of making ineffective the second source of illusions mentioned above. Only after the meeting with his double, can he eliminate what comes from himself and thus he will be able to remove the second source of delusion when he has acquired the faculty for judging by the very nature of a fact seen in the supersensible world, whether it is a reality or an illusion. Now if the illusions were of precisely the same appearance as the realities, differentiation would be impossible. But this is not the case. Illusions of the supersensible world have in themselves qualities which distinguish them definitely from the realities, and the important thing is for the occult student to know by what qualities he may be able to recognize those realities.