The singular-plural distinction is universal in free personal pronouns in the 1st person.
Standardized
IF there is a singular-plural distinction in the 2nd and/or the 3rd person of personal pronouns, THEN there is a singular-plural distinction in the 1st person.
Keywords
number, singular, plural, pronoun, personal pronoun, person, 1, 2, 3
Chinese Pidgin English (see Forchheimer 1953: 12, also mentioned in Moravcsik 1978b: 352);In Pirahã (Mura, Paezan) there are only three forms of personal pronouns: 1st, 2nd, and 3rd. There are no special plural forms for these pronouns. Generally, 1Pl and 2Pl are expressed periphrastically. Ex. 1INCL is expressed by the conjunction of 1st and 2nd person forms. (Everett 1986: 280-1).Javanese (Sundic, Austronesian) has only three personal pronouns:1st, 2nd and 3rd person (Uhlenbeck 1978; Uspenky was the first one who noted this feature of Javanese, see #517). Marind (Trans-New Guinea) differentiates number in 2nd and 3rd, but not in 1st person(Drabbe 1955 [Boelaars 1950: 2], mentioned in Clenova 1973: 174).
As restated in Standardized, this is a paradox of material implication: according to Original, the implicatum is always true.