In every department of physical science there is only so much science, properly so-called, as there is mathematics. – Immanuel Kant
Experience without theory is blind, but theory without experience is mere intellectual play. – Immanuel Kant
Intuition and concepts constitute… the elements of all our knowledge, so that neither concepts without an intuition in some way corresponding to them, nor intuition without concepts, can yield knowledge. – Immanuel Kant
All our knowledge begins with the senses, proceeds then to the understanding, and ends with reason. There is nothing higher than reason. – Immanuel Kant