If people had even the smallest inkling of what it means to think in the spirit, to live in the spirit, using the physical body only as an instrument, — so that one does not feel firmly fastened into it, identifying oneself with it — they would sing psalms about the misery of having to use a male body in an incarnation, for of course these material effects have also filtered into the brain.
One observes that the forms of the male brain, through having been deeper into matter, are more difficult to manage than the more flexible forms of the female brain. It is truly a more difficult matter to train a male brain for the ascent into the higher worlds, and to translate the truths into thoughts, than it is to train a female brain for the same purpose.
For this reason it is not surprising to people who think, when a new conception of the world arises such as that of Spiritual Science, it is more easily grasped by the more manageable female brain; for it is more difficult for the male brain, being less pliable and obedient, to free itself from certain thoughts which it has absorbed.
Hence Spiritual Science will not find an easy acceptance amongst the men who are to-day the leaders of culture and of the cultured ideas prevalent in our day. We must realise how awkward an instrument is the brain of a learned man to-day, not only for the acceptance of Spiritual Science, but also for thinking along those lines.
But we must not look at these things in a wrong way and draw our own conclusions — rather should we look upon it as all the more significant that there are so many men whose brains are so pliant that they have become intimately acquainted with Spiritual Science.
Source: Rudolf Steiner – GA 116 – The Christ impulse and the development of the Ego-Consciousness – Lecture 5 – Berlin, 9th March 1910