Immanuel Kant

Human reason, in one sphere of its cognition, is called upon to consider questions, which it cannot decline, as they are presented by its own nature, but which it cannot answer, as they transcend every faculty of the mind.

our knowledge may relate to objects, it is at least quite clear that the only manner in which it immediately relates to them is by means of an intuition

hat there are two sources of human knowledge

By the former, objects are given to us; by the latter, thought.

The transcendental doctrine of sense must form the first part of our science of elements, because the conditions under which alone the objects of human knowledge are given must precede those under which they are thought

Introduction by itself could be an antidote, however weak, for an age excelling so often in the cult of unreason.