In this brief chapter we cannot attempt to go into details, and in speaking of the morphology of vulgar Latin we must content ourselves with sketching its general characteristics and tendencies, as we have done in the case of its phonology. In English our inflectional forms have been reduced to a minimum, and consequently there is little scope for differences in this respect between the written and spoken languages. From the analogy of other forms the illiterate man occasionally says: "I swum," or, "I clumb," or "he don't," but there is little chance of making a mistake. However, with three genders, five declensions for nouns, a fixed method of comparison for adjectives and adverbs, an elaborate system of pronouns, with active and deponent, regular and irregular verbs, four conjugations, and a complex synthetical method of forming the moods and tenses, the pitfalls for the unwary Roman were without number, as the present-day student of Latin can testify to his sorrow. That the man in the street, who had no newspaper to standardize his Latin, and little chance to learn it in school, did not make more mistakes is surprising. In a way many of the errors which he did make were historically not errors at all. This fact will readily appear from an illustration or two. In our survey of preliterary Latin we had occasion to notice that one of its characteristics was a lack of fixity in the use of forms or constructions. In the third century before our era, a Roman could say audibo or audiam, contemplor or contemplo, senatus consultum or senati consultum. Thanks to the efforts of the scientific grammarian, and to the systematizing influence which Greek exerted upon literary Latin, most verbs were made deponent or active once for all, a given noun was permanently assigned to a particular declension, a verb to one conjugation, and the slight tendency which the language had to the analytical method of forming the moods and tenses was summarily checked. Of course the common people tried to imitate their betters in all these matters, but the old variable usages persisted to some extent, and the average man failed to grasp the niceties of the new grammar at many points. His failures were especially noticeable where the accepted literary form did not seem to follow the principles of analogy. When these principles are involved, the common people are sticklers for consistency. The educated man conjugates: "I don't," "you don't," "he doesn't," "we don't," "they don't"; but the anomalous form "he doesn't" has to give way in the speech of the average man to "he don't." To take only one illustration in Latin of the effect of the same influence, the present infinitive active of almost all verbs ends in -re, e.g., amare, monere, and regere. Consequently the irregular infinitive of the verb "to be able," posse, could not stand its ground, and ultimately became potere in vulgar Latin. In one respect in the inflectional forms of the verb, the purist was unexpectedly successful. In comedy of the third and second centuries B.C., we find sporadic evidence of a tendency to use auxiliary verbs in forming certain tenses, as we do in English when we say: "I will go," "I have gone," or "I had gone." This movement was thoroughly stamped out for the time, and does not reappear until comparatively late.
In Latin there are three genders, and the grammatical gender of a noun is not necessarily identical with its natural gender. For inanimate objects it is often determined simply by the form of the noun. Sella, seat, of the first declension, is feminine, because almost all nouns ending in -a are feminine; hortus, garden, is masculine, because nouns in -us of its declension are mostly masculine, and so on. From such a system as this two results are reasonably sure to follow. Where the gender of a noun in literary Latin did not conform to these rules, in popular Latin it would be brought into harmony with others of its class. Thus stigma, one of the few neuter nouns in -a, and consequently assigned to the third declension, was brought in popular speech into line with sella and the long list of similar words in -a, was made feminine, and put in the first declension. In the case of another class of words, analogy was supplemented by a mechanical influence. We have noticed already that the tendency of the stressed syllable in a word to absorb effort and attention led to the obscuration of certain final consonants, because the final syllable was never protected by the accent. Thus hortus in some parts of the Empire became hortu in ordinary pronunciation, and the neuter caelum, heaven, became caelu. The consequent identity in the ending led to a confusion in the gender, and to the ultimate treatment of the word for "heaven" as a masculine. These influences and others caused many changes in the gender of nouns in popular speech, and in course of time brought about the elimination of the neuter gender from the neo-Latin languages.
Something has been said already of the vocabulary of the common people. It was naturally much smaller than that of cultivated people. Its poverty made their style monotonous when they had occasion to express themselves in writing, as one can see in reading St. Ætheria's account of her journey to the Holy Land, and of course this impression of monotony is heightened by such a writer's inability to vary the form of expression. Even within its small range it differs from the vocabulary of formal Latin in three or four important respects. It has no occasion, or little occasion, to use certain words which a formal writer employs, or it uses substitutes for them. So testa was used in part for caput, and bucca for os. On the other hand, it employs certain words and phrases, for instance vulgar words and expletives, which are not admitted into literature.
In its choice of words it shows a marked preference for certain suffixes and prefixes. It would furnish an interesting excursion into folk psychology to speculate on the reasons for this preference in one case and another. Sometimes it is possible to make out the influence at work. In reading a piece of popular Latin one is very likely to be impressed with the large number of diminutives which are used, sometimes in the strict sense of the primitive word. The frequency of this usage reminds one in turn of the fact that not infrequently in the Romance languages the corresponding words are diminutive forms in their origin, so that evidently the diminutive in these cases crowded out the primitive word in popular use, and has continued to our own day. The reason why the diminutive ending was favored does not seem far to seek. That suffix properly indicates that the object in question is smaller than the average of its kind. Smallness in a child stimulates our affection, in a dwarf, pity or aversion. Now we give expression to our emotion more readily in the intercourse of every-day life than we do in writing, and the emotions of the masses are perhaps nearer the surface and more readily stirred than are those of the classes, and many things excite them which would leave unruffled the feelings of those who are more conventional. The stirring of these emotions finds expression in the use of the diminutive ending, which indirectly, as we have seen, suggests sympathy, affection, pity, or contempt. The ending -osus for adjectives was favored because of its sonorous character. Certain prefixes, like de-, dis-, and ex-, were freely used with verbs, because they strengthened the meaning of the verb, and popular speech is inclined to emphasize its ideas unduly.
To speak further of derivation, in the matter of compounds and crystallized word groups there are usually differences between a spoken and written language. The written language is apt to establish certain canons which the people do not observe. For instance, we avoid hybrid compounds of Greek and Latin elements in the serious writing of English. In formal Latin we notice the same objection to Greco-Latin words, and yet in Plautus, and in other colloquial writers, such compounds are freely used for comic effect. In a somewhat similar category belong the combinations of two adverbs or prepositions, which one finds in the later popular Latin, some of which have survived in the Romance languages. A case in point is ab ante, which has come down to us in the Italian avanti and the French avant. Such word-groups are of course debarred from formal speech.
In examining the vocabulary of colloquial Latin, we have noticed its comparative poverty, its need of certain words which are not required in formal Latin, its preference for certain prefixes and suffixes, and its willingness to violate certain rules, in forming compounds and word-groups, which the written language scrupulously observes. It remains for us to consider a third, and perhaps the most important, element of difference between the vocabularies of the two forms of speech. I mean the use of a word in vulgar Latin with another meaning from that which it has in formal Latin. We are familiar enough with the different senses which a word often has in conversational and in literary English. "Funny," for instance, means "amusing" in formal English, but it is often the synonym of "strange" in conversation. The sense of a word may be extended, or be restricted, or there may be a transfer of meaning. In the colloquial use of "funny" we have an extension of its literary sense. The same is true of "splendid," "jolly," "lovely," and "awfully," and of such Latin words as "lepidus," "probe," and "pulchre." When we speak of "a splendid sun," we are using splendid in its proper sense of shining or bright, but when we say, "a splendid fellow," the adjective is used as a general epithet expressing admiration. On the other hand, when a man of a certain class refers to his "woman," he is employing the word in the restricted sense of "wife." Perhaps we should put in a third category that very large colloquial use of words in a transferred or figurative sense, which is illustrated by "to touch" or "to strike" when applied to success in getting money from a person. Our current slang is characterized by the free use of words in this figurative way.