There are special rules which must be observed both by speakers and writers. Language is based on reason, antiquity, authority and usage. Reason finds its chief support in analogy and sometimes in etymology. As for antiquity, it is commended to us by the possession of a certain majesty, I might almost say sanctity.

Authority as a rule we derive from orators and historians. For poets, owing to the necessities of metre, are allowed a certain licence except in cases where they deliberately choose one of two expressions, when both are metrically possible, as for instance in imo de stirpe recisum and aeriae quo congessere palumbes or silice in nuda Aen. xii. 208: cutaway from the lowest root. Ecl. iii. 69: where airy doves have made their nest. Ecl. i. 15: on the naked rock. Stirps, palumbes and silex are usually masculine. and the like. The judgment of a supreme orator is placed on the same level as reason, and even error brings no disgrace, if it result from treading in the footsteps of such distinguished guides.

Usage however is the surest pilot in speaking, and we should treat language as currency minted with the public stamp. But in all these cases we have need of a critical judgment, especially as regards analogy (a Greek term for which a Latin equivalent has been found in proportion).

The essence of analogy is the testing of all subjects of doubt by the application of some standard of comparison about which there is no question, the proof that is to say of the uncertain by reference to the certain. This can be done in two different ways: by comparing similar words, paying special attention to their final syllables (hence monosyllables are asserted to lie outside the domain of analogy sc. because two monosyllables, unless identical, cannot have the same final syllable. ) and by the study of diminutives.

Comparison of nouns will reveal either their gender or their declension: in the first case, supposing the question is raised as to whether junis be masculine or feminine, panis will supply a standard of comparison: in the second case, supposing we are in doubt as to whether we should say hac domu or hac domo, domuum or domorum, the standard of comparison will be found in words such as anus or manus.

Diminutives merely reveal the gender: for instance, to return to a word previously used as an illustration, funiculus proves that funis is masculine.

The same standard may be applied in the case of verbs. For instance if it should be asserted that the middle syllable of fervere is short, we can prove this to be an error, because all verbs which in the indicative terminate in -eo, make the middle syllable of the infinitive long, if that syllable contain an e: take as examples such verbs as prandeo, pendeo, spondeo with infinitives prandēre, pendēre, spondēre.

Those verbs, however, which terminate in -o alone, if they form the infinitive in e, have the e short; compare lego, dico, curro, with the infinitives, legĕre, dicĕre, currĕre. I admit that in Lucilius we find— fervit aqua et fervet: firvit nunc ferverit ad annum. In Book IX. The water boils and boil it will; it boils and for a year will boil. But with all due respect to so learned a man, if he regards fervit as on the same footing as currit and legit, we shall say fervo as we say lego and curro: but such a form has never yet come to my ears.

But this is not a true comparison: for fervit resembles servit, and on this analogy we should say fervire like servire.

It is also possible in certain cases to discover the present indicative of a verb from the study of its other tenses. I remember, for instance, refuting certain scholars who criticised me for using the word pepigi: for, although they admitted that it had been used by some of the best authors, they asserted that it was an irrational form because the present indicative paciscor, being passive in form, made pactus sum as its perfect.

I in addition to quoting the authority of orators and historians maintained that I was also supported by analogy. For when I found ni ita pacunt in the Twelve Tables, I noted that cadunt provided a parallel: it was clear therefore that the present indicative, though now obsolete, was paco on the analogy of cado, and it was further obvious that we say pepigi for just the same reason that we say cecidi.

But we must remember that analogy cannot be universally applied, as it is often inconsistent with itself. It is true indeed that scholars have attempted to justify certain apparent anomalies: for example, when it is noted to what an extent lepus and lupus, which resemble each other closely in the nominative, differ in the plural and in the other cases, they reply that they are not true parallels, since lepus is epicene, while lupus is masculine, although Varro in the book in which he narrates the origins of Rome, writes lupus femina, following the precedent of Ennius and Fabius Pictor.

The same scholars, however, when asked why aper became apri in the genitive, but pater patris, asserted that aper was an absolute, pater a relative noun. Further since both words derive from the Greek, they took refuge in the fact that πατρός provides a parallel to patris and κάπρου to apri.

But how will they evade the difficulty that feminine nouns whose nominative singular ends in -us never make the genitive end in -ris, and yet the genitive of Venus is Veneris: again nouns ending in -es have various genitive terminations, but never end in -ris, but yet we have no choice but to make the genitive of Ceres Cereris?

Again what of those words which, although identical in the form of the nominative or present indicative, develop the utmost variety in their inflections. Thus from Alba we get both Albanus and Albensis, from volo both volui and volavi. Analogy itself admits that verbs whose present indicative ends in -o have a great variety of perfect formations, as for instance cado cecidi, spondeo spopondi, pingo pinxi, lego legi, pono posui, fiango fregi, laudo laudavi.

For analogy was not sent down from heaven at the creation of mankind to frame the rules of language, but was discovered after they began to speak and to note the terminations of words used in speech. It is therefore based not on reason but on example, nor is it a law of language, but rather a practice which is observed, being in fact the offspring of usage.

Some scholars, however, are so perverse and obstinate in their passion for analogy, that they say audaciter in preference to audacter, the form preferred by all orators, and emicavit for emicuit, and conire for coire. We may permit them to say audivisse, scivisse, tribunale and faciliter, nor will we deprive them of frugalis as an alternative for frugi:

for from what else can frugalitas be formed? They may also be allowed to point out that phrases such as centum milia nummum and fidem deum i.e. nummum and deum should, strictly speaking, be accus. singular. involve a double solecism, since they change both case and number. Of course we were in blank ignorance of the fact and were not simply conforming to usage and the demands of elegance, as in the numerous cases, with which Cicero deals magnificently, as always, in his Orator. xlvi. 155.

Augustus again in his letters to Gaius Caesar corrects him for preferring calidus to caldus, not on the ground that the former is not Latin, but because it is unpleasing and as he himself puts it in Greek περίεργον (affected).

Some hold that this is just a question of ὀρθοέπεια or correctness of speech, a subject to which I am far from being indifferent. For what can be more necessary than that we should speak correctly? Nay, I even think that, as far as possible, we should cling to correct forms and resist all tendencies to change. But to attempt to retain forms long obsolete and extinct is sheer impertinence and ostentatious pedantry.