The more advanced soul is clearly the one that comes to sound judgments out of its ordinary understanding — and this ordinary understanding is completely sufficient to grasp spiritual science if one is free of preconceived notions. We are making a great mistake if we allow atavistic clairvoyant abilities to impress us. We are on the wrong track if we believe such a person’s soul is particularly advanced. That this soul shows such abilities means that it has failed to go through certain things that had to be experienced in the age of clairvoyance. Therefore, that soul is now catching up on what was missed earlier. It is quite grotesque when people involved in spiritual science believe that someone who displays a certain clairvoyance without having studied spiritual science must have been someone important in a previous life. Such a person was quite certainly less important than someone displaying sound judgment about things.
Source (German): Rudolf Steiner – GA 154 – Wie erwirbt man sich Verständnis für die geistige Welt? – Berlin 18 April 1914 (p 25)