Common sense

Even the Initiate, if he has not developed his reason in the right way, gains nothing whatever from his super-sensible experiences. When someone today — please take what I am now saying as a really serious matter — has learnt to think in a way perfectly adapted to meeting the demands of school examinations, when he acquires habits of thought that enable him to pass academic tests with flying colours — then his reasoning faculty will be so vitiated that even if millions of experiences of the super-sensible world were handed to him on a platter, he would see them as little as you could physically see the objects in a dark room.

Source: Rudolf Steiner – GA 196 – Some Conditions for Understanding Supersensible Experiences – Dornach, 18th January 1920