defining ideas that are irrelevant to the proposition as a
whole but that give a radical element a particular increment of
significance and that are thus inherently related in a specific way
to concepts of type I[65]

III. _Concrete Relational Concepts_ (still more abstract, yet not
entirely devoid of a measure of concreteness): normally expressed by
affixing non-radical elements to radical elements, but generally at
a greater remove from these than is the case with elements of type
II, or by inner modification of radical elements; differ
fundamentally from type II in indicating or implying relations that
transcend the particular word to which they are immediately
attached, thus leading over to

IV. _Pure Relational Concepts_ (purely abstract): normally expressed by
affixing non-radical elements to radical elements (in which case
these concepts are frequently intertwined with those of type III) or
by their inner modification, by independent words, or by position;
serve to relate the concrete elements of the proposition to each
other, thus giving it definite syntactic form.

[Footnote 64: Except, of course, the fundamental selection and contrast
necessarily implied in defining one concept as against another. "Man"
and "white" possess an inherent relation to "woman" and "black," but it
is a relation of conceptual content only and is of no direct interest to
grammar.]

[Footnote 65: Thus, the _-er_ of _farmer_ may he defined as indicating
that particular substantive concept (object or thing) that serves as the
habitual subject of the particular verb to which it is affixed. This
relation of "subject" (_a farmer farms_) is inherent in and specific to
the word; it does not exist for the sentence as a whole. In the same way
the _-ling_ of _duckling_ defines a specific relation of attribution
that concerns only the radical element, not the sentence.]

The nature of these four classes of concepts as regards their
concreteness or their power to express syntactic relations may be thus
symbolized:
_
Material _/ I. Basic Concepts
Content \_ II. Derivational Concepts
_
Relation _/ III. Concrete Relational Concepts
\_ IV. Pure Relational Concepts

These schemes must not be worshipped as fetiches. In the actual work of
analysis difficult problems frequently arise and we may well be in doubt
as to how to gro