I’m reading some Descartes today, and I notice that he has a very calming effect. Even when he’s making what are, on the face of it, outrageous claims for his philosophy, he strikes one as humble and level-headed. This is very similar to Anselm, in my experience. Also, Descartes and Anselm share an emphasis on the pleasure to be derived from speculative thought.
Perhaps there’s something about arriving at the ontological proof of the existence of God that makes one easy-going and pleasant to be around (or at least read).