Conjugation and declension constitute inflection. Nouns and verbs, speaking generally, are inflected.
Inflection, a part of derivation in its wider sense, is separated from derivation properly so called, or from derivation in its limited sense.
The degrees of comparison, or certain derived forms of adjectives; the ordinals, or certain derived forms of the numerals; the diminutives, &c., or certain derived forms of the substantive, have been separated from derivation properly so called, and considered as parts of inflection. I am not certain, however, that for so doing there is any better reason than mere convenience.
Derivation proper, the subject of the present chapter, comprises all the changes that words undergo, which are not referable to some of the preceding heads. As such, it is, in its details, a wider field than even composition. The details, however, are not entered into.
[§ 372]. Derivation proper may be divided according to a variety of principles. Amongst others—
I. According to the evidence.—In the evidence that a word is not simple, but derived, there are at least two degrees.
a. That the word strength is a derived word I collect to a certainty from the word strong, an independent form, which I can separate from it. Of the nature of the word strength there is the clearest evidence, or evidence of the first degree.
b. Fowl, hail, nail, sail, tail, soul; in Anglo-Saxon, fugel, hægel, nægel, segel, tægel, sawel.—These words are by the best grammarians considered as derivatives. Now, with these words I cannot do what was done with the word strength, I cannot take from them the part which I look upon as the derivational addition, and after that leave an independent word. Strength -th is a true word; fowl or fugel -l is no true word. If I believe
these latter words to be derivations at all, I do it because I find in words like harelle, &c., the -l as a derivational addition. Yet, as the fact of a word being sometimes used as a derivational addition does not preclude it from being at other times a part of the root, the evidence that the words in question are not simple, but derived, is not cogent. In other words, it is evidence of the second degree.