Miscellanies 2.4.14

So only by faith is it possible to reach the first principle of the universe. For all knowledge can be taught, and what can be taught comes from what is already known. But the first principle of the universe was not known beforehand to the Greeks; not to Thales, who thought water the first cause, nor to the other natural philosophers after him. For even if Anaxagoras was the first to set mind over things, even he did not keep to the efficient cause, painting some senseless vortexes, together with the inactivity and folly of mind. That is why the Word says, “Call no one on earth your teacher.” For knowledge is a demonstrative state, but faith is a grace that raises from indemonstrable things to the universal, the simple, which is neither with matter, nor matter, nor subject to matter.