1. In Sanskrit there are two forms, a) kataras, the same word as whether, meaning which out of two; b) katamas, which out of many. So also êkateras, one out of two; êkatamas, one out of many. In Greek, the Ionic form κότερος (πότερος); in Latin, uter, neuter, alter; and in Mœso-Gothic, hvathar, have the same form and the same meaning.
2. In the Scandinavian language the word anden, Dano-Saxon annar, Iceland corresponds to the English word second, and not the German zweite: e. g., Karl den Anden, Charles the Second. Now anthar is the older form of other.
B. Secondly, it may be stated of them, that the termination -er is the same termination that we find in the comparative degree.
1. The idea expressed by the comparative degree is the comparison, not of many, but of two things; this is better than that.
2. In all the Indo-European languages where there are pronouns in -ter, there is also a comparative degree in -ter. See next chapter.
3. As the Sanskrit form kataras corresponds with the comparative degree, where there is the comparison of two things with each other; so the word katamas is a superlative form; and in the superlative degree lies the comparison of many things with each other.
Hence other and whether (to which may be added either and neither) are pronouns with the comparative form.
Other has the additional peculiarity of possessing the plural form others. Hence, like self, it is, in the strictest sense, a substantival pronoun.