place, keep its radical concepts pure or does it build up its
concrete ideas by an aggregation of inseparable elements (types A and C
_versus_ types B and D)? And, in the second place, does it keep the
basic relational concepts, such as are absolutely unavoidable in the
ordering of a proposition, free of an admixture of the concrete or not
(types A and B _versus_ types C and D)? The second question, it seems to
me, is the more fundamental of the two. We can therefore simplify our
classification and present it in the following form:
_
I. Pure-relational _/ A. Simple
Languages \_ B. Complex
_
II. Mixed-relational _/ C. Simple
Languages \_ D. Complex

The classification is too sweeping and too broad for an easy,
descriptive survey of the many varieties of human speech. It needs to be
amplified. Each of the types A, B, C, D may be subdivided into an
agglutinative, a fusional, and a symbolic sub-type, according to the
prevailing method of modification of the radical element. In type A we
distinguish in addition an isolating sub-type, characterized by the
absence of all affixes and modifications of the radical element. In the
isolating languages the syntactic relations are expressed by the
position of the words in the sentence. This is also true of many
languages of type B, the terms "agglutinative," "fusional," and
"symbolic" applying in their case merely to the treatment of the
derivational, not the relational, concepts. Such languages could be
termed "agglutinative-isolating," "fusional-isolating" and
"symbolic-isolating."

This brings up the important general consideration that the method of
handling one group of concepts need not in the least be identical with
that used for another. Compound terms could be used to indicate this
difference, if desired, the first element of the compound referring to
the treatment of the concepts of group II, the second to that of the
concepts of groups III and IV. An "agglutinative" language would
normally be taken to mean one that agglutinates all of its affixed
elements or that does so to a preponderating extent. In an
"agglutinative-fusional" language the derivational elements are
agglutinated, perhaps in the form of prefixes, while the relational
elements (pure or mixed) are fused with the radical element, possibly as
another set of prefixes following the first set or in the
form of suffixes or as part prefi