Mysticism

In every major religious movement, runs a trend towards so-called mysticism. Ecstatic movements and some forms of monasticism in Christianity, Sufism in Islam, Kaballah in Judaism, etc.

Can a Latter-day Saint gain any insight, learn any truth, from mysticism? Or should it all, like seances and ouija boards, be left alone as utterly incompatible with our faith?

I ask because my personal study of history and literature has now brought me to the Middle Ages, when Christian mysticism was all the rage, and I would like to understand its foundations. I read 30 pages of Dionysus the Areopagite's "The Divine Names" today and understood virtually nothing of it -- it seemed as bizzare and contradictory as the Tao philosophy of China. Clearly, some mental effort will be required to gain even a basic understanding.