In Homeric Greek the dual number is not used regularly, and the principles underlying its alternation with the plural are not clear. We argue that the use of the dual abides by two main functions. Syntactically, the dual tends to appear in the first mention of a noun phrase, which is resumed by the plural in the following occurrences. Semantically, the dual is preferred for nominals denoting human and prominent participants. The plausibility of this distribution is corroborated by cross-linguistic parallels, since many languages use the dual or other minor numbers under the same circumstances as Homeric Greek.