Rudolf Steiner: "In spiritual investigation when such a question arises it must first of all be thoroughly experienced. One must live into it. If one begins to speculate as to a possible solution to such a question, as to a possible answer, one will certainly arrive at a false conclusion. For the effort of the ordinary brain-fettered understanding gives, as a rule, no solution. That can only be ascertained through inner activity. The answers to questions relating to the enigmas of the spiritual world descend from the spiritual world as by an act of grace. One must wait. There is really nothing else to be done but to live with the question and meditate on it again and again. Let it live in the soul with all the feelings aroused by it, and then calmly wait; wait till one is worthy — that is the right word — worthy to receive an answer from the spiritual world. And, as a rule, this comes from quite a different quarter than one would expect. Thus the answer comes from the spiritual world at the right moment, that is, at the moment when one has sufficiently prepared one's soul to receive the answer. As to whether it is then the right answer can as little be decided theoretically as can any statement concerning physical reality; experience alone can furnish the criterion. To those who are always denying spiritual reality by saying ‘That cannot be proved; and everything must be proved,’ I should like to put one question: Would it have been possible to prove the existence of a whale in the physical world if none had ever been discovered? Nothing can be proved, unless it can be shown in the same way as a reality; even in the spiritual world one must experience that which is reality."