When I say "I", I mean "you": public service hortatives in French

A lot of languages - Indonesian, for instance - make a rather useful distinction between two 1st person plural pronouns: "we (including you)" and "we (excluding you)". A few languages, such as Nivkh, extend this distinction to the singular, sort of, having a dual 1st person inclusive pronoun "I and you" alongside a singular 1st person exclusive pronoun "I" (and no other duals). But a 1st person singular inclusive pronoun, strictly speaking, is a contradiction in terms: it would have to be a pronoun referring to only one person which included both the speaker and the addressee.

Or is it? There are a couple of ways in which this apparent contradiction could be resolved. The most obvious would be if you had a special pronoun used only when the speaker was also the addressee; but, as such a form would be used only in talking to oneself, it would be unlikely to catch on enough to become part of the language. Less obviously, however, you could have a singular pronoun being used in a sufficiently vague way to refer to both the speaker and the addressee (but not to an uninvolved third person.)

Soon after moving to France, I realised that, in public announcements, this is in fact what French does with its 1st person singular pronoun je. The realisation was prompted by a poster in a medical insurance office saying, in big letters, something like:

Je choisis le générique, je ne fais pas d'avance de frais.
(I choose generic drugs, I pay no advance.)

This was clearly not a piece of self-observation someone had put up; rather, it was intended to tell us "Choose generic drugs, and pay no advance". Over the following days, I noticed that concealed exhortations of this form were everywhere: Oui je vote (Yes I vote), En car comme en voiture, je boucle ma ceinture (In a coach as in a car, I buckle my seatbelt), ... All easily understandable as conveying the message is "I do this, and so should you". But in English, you consistently cast such messages in the imperative, with no "I" at all: "Please take a moment to cast your vote in this important election" or "Buckle up, it's the law", and so on. One obvious side effect is that the slogan "Je suis Charlie" has at least one reading directly accessible to French speakers but not to English speakers who understand it word for word: namely, "I am Charlie, and you'd better be Charlie too".

The difference between the two languages in this respect is at the level of pragmatics, for now. But if such hortatives become sufficiently common in French, one could well imagine the construction grammaticalising further and even eventually becoming distinct from ordinary 1st person marking. In that case, we might end up with a true 1st person singular inclusive pronoun: a pronoun that simultaneously means "I" and "you", while taking strict singular agreement. Give it another 500 years...

Are you familiar with another language that does this?

The puzzle of the extra pronouns

Like most (all?) Songhay languages, Kwarandzie has two sets of 3rd person pronouns: in this case, they are a (sg.) / i (pl.) vs. ana / ini. In southern Songhay (eg Koyra Chiini, the longer set are used as logophors - that is, used to refer back to the speaker in reported speech. This is not the case in Kwarandzie, though.

ana/ini are obligatory in pre-sentential topic and focus position (including when followed by a preposition), while a/i are obligatory for possessors:

ana (*a) a e-kka. ghi "it's him that hit me."
ini (*i) i-bbey ibbagen "them, they know tales."
an (*anan) kembi "his hand"

But in normal object position, either set can occur:

e-ggwa / e-ggwana "he saw him"

After much checking, I still have no idea what factors drive the selection of one or the other in this position. These are not used, Algonquian-style, for tracking two distinct referents: ²e-gga.r.ana ²e-kka.r.a "I found him and hit him" can as easily refer to hitting the same person as to two different objects.

So it's not logophoricity (much less reflexives), it's not an obviative or a switch-reference system, it's not related to politeness or gender... can anyone think of another possibility for me to check before I leave?

Malay pronouns

And as long as I'm comparing pronouns, it seems only fair to note that not all languages have nice stable uncomplicated pronouns like Beja. Japanese is an obvious counterexample, but Prentiss Riddle and Macvaysia point out an egregious case in Malay... (noticed thanks to Language Hat.) I was especially struck by the "distinct set reserved just for addressing ethnic Chinese" - if I'm not mistaken, those are clear borrowings from Hokkien Chinese (where "I" is goá, "you" is lí.)