The conception will be made clearer when it is remembered that Aquinas, taught by the mysterious author of the writings of the pseudo-Dionysius, who so marvellously influenced medieval writers, sometimes spoke of a natural revelation, or of reason as a source of truths in themselves mysterious, and was always accustomed to say that reason as well as revelation contained two kinds of knowledge.
They have all kinds of good stuff.
I've been doing a lot of fishing, of both kinds this week.
I love all kinds of music.
Now, we stumble upon these kinds of causal associations almost as an accident.