They educate both the Understanding and the Reason. Every property of matter is a school for the understanding, — its solidity or resistance, its inertia, its extension, its figure, its divisibility. The understanding adds, divides, combines, measures, and finds nutriment and room for its activity in this worthy scene. Meantime, Reason transfers all these lessons into its own world of thought, by perceiving the analogy that marries Matter and Mind.
Understanding: the ability to deduce, judge
Reason: the ability to infer, using logic and mind rather than empiricism
might need to actually read kant at some point