  In the realm of intellects, Dietrich tells us, we discover a fourfold order in which intellectual reality stands: at the top of this order is found what Dietrich calls intellects existing through their essence, followed by intelligent spiritual substances that are called angels, and then species and finally the individual realities included in species that are known to mind. There are three kinds of intellects that exist through their essence: the separated intelligences, celestial bodies, and human intellects.