Consider the long conceptual chain that starts from simple, ostensive
definitions and rises to higher and still higher concepts, forming a
hierarchical structure of knowledge so complex that no electronic computer
could approach it. It is by means of such chains that man has to acquire and
retain his knowledge of reality.
Yet this is the simpler part of his psycho-epistemological task. There is
another part which is still more complex.
The other part consists of applying his knowledge—i.e., evaluating the facts
of reality, choosing his goals and guiding his actions accordingly. To do that,
man needs another chain of concepts, derived from and dependent on the first,
yet separate and, in a sense, more complex: a chain of normative
While cognitive abstractions identify the facts of reality, normative
abstractions evaluate the facts, thus prescribing a choice of values and a
course of action. Cognitive abstractions deal with that which is; normative
abstractions deal with that which ought to be (in the realms open to man’s