Rav Kook on Mysticism and Secular Studies

I just came across a fascinating letter on Chardal blog (tr. Bezalel Naor). In it he emphasizes that one should spend the majority of one's time (assuming one has the inclination) learning to know one's Creator, as R' Chaim Vital says in the beginning of the Etz Chaim. Towards that end, secular studies may also be useful. See there for the full letter, it's well worth reading