All that man learns intellectually about metaphysics keeps him limited to book-learning. He derives no benefit but a passing interest; it is a surprise to him to know that there are so many different planes of our being. He does not go further, and if he wanted to see them and know what they are, he could not. But by meditation he can realize them, and by this realization he can give the interpretation of any philosophy, whether Buddhist, or ancient Greek, or Vedanta philosophy, any philosophy you put before him, for he knows what he has experienced through meditation.