There is another expedient for denoting the different qualities of different substances, which as it requires no abstraction, nor any conceived separation of the quality from the subject, seems more natural than the invention of nouns adjective, and which, upon this account, could hardly fail, in the first formation of language, to be thought of before them. This expedient is to make some variation upon the noun substantive itself, according to the different qualities which it is endowed with. Thus, in many languages, the qualities both of sex and of the want of sex, are expressed by different terminations in the nouns substantive, which denote objects so qualified. In Latin, for example, _lupus_, _lupa_; _equus_, _equa_; _juvencus_, _juvenca_; _Julius_, _Julia_; _Lucretius_, _Lucretia_, &c. denote the qualities of male and female in the animals and persons to whom such appellations belong, without needing the addition of any adjective for this purpose. On the other hand, the words _forum_, _pratum_, _plaustrum_, denote by their peculiar termination the total absence of sex in the different substances which they stand for. Both sex, and the want of all sex, being naturally considered as qualities modifying and inseparable from the particular substances to which they belong, it was natural to express them rather by a modification in the noun substantive, than by any general and abstract word expressive of this particular species of quality. The expression bears, it is evident, in this way, a much more exact analogy to the idea or object which it denotes, than in the other. The quality appears, in nature, as a modification of the substance, and as it is thus expressed, in language, by a modification of the noun substantive, which denotes that substance, the quality and the subject are, in this case, blended together, if I may say so, in the expression, in the same manner, as they appear to be in the object and in the idea. Hence the origin of the masculine, feminine, and neutral genders, in all the ancient languages. By means of these, the most important of all distinctions, that of substances into animated and inanimated, and that of animals into male and female, seem to have been sufficiently marked without the assistance of adjectives, or of any general names denoting this most extensive species of qualifications.