History: only

Ways to say only:

• po'o
  • la djan po'o klama le zarci
  • la djan joi la meris po'o klama le zarci
• ropa
  • ??
• du ro
  • la djan du ro le klama be le zarci
  • la djan joi la meris du ro le klama be le zarci
• pamei
  • ??
• romei
  • la djan romei lei klama be le zarci
  • la djan joi la meris romei lei klama be le zarci
• .e no drata
  • la djan e no drata cu klama le zarci
  • la djan joi la meris e no drata cu klama le zarci
• se steci : x1 is/are the only one(s) with property x2 among x3
  • la djan se steci le ka ce'u klama le zarci
  • la djan joi la meris se steci le ka ce'u klama le zarci

I never see ro le broda being used for a single broda, for example, and it is rare to find le broda referring to more than one.

ro le broda is going to be pretty non-intuitive to non-natives. It also has some potential to be accidentally wrong. --jay

I've had occasion to do that to the past (I assume you're referring to ro le broda as a singular), because I predate po'o, and never liked it. (In fact, I transferred my Lojban for 'only' (.e no drata) into Klingon, because I'd mislearnt that neH meant po'o after nouns, not .uenai (merely) as it does after verbs.) At any rate, I had said in the past "all one of them", but in that case I certainly said the "one": ropa le broda. See http://balance.wiw.org/~jkominek/lojban/9201/msg00039.html, and ropa and ropamei in the archives. (I'm seeing Nora in http://balance.wiw.org/~jkominek/lojban/9602/msg00273.html saying ropa should be 'any one of', but surely that's silly. To my unsurprise, ropa is unmentioned in the refgramm.) — nitcion

ro pa broda cu brode might mean that only one broda is a brode, (i.e., no other broda) but not that one broda is the only one that is a brode. Indeed ro is redundant there, because pa by itself already means one and only one.

• But that's why 'ropa' shouldn't just mean 'all of the one and only one', but 'all of them — i.e. one and only one'. That way, ro pa broda cu brode is true when both ro broda cu brode is true and pa broda cu brode is true. Because ro and pa are both digits, this is not an issue for quantification scope: ro pa broda != ro lo pa broda. None of this is codified in the refgramm, mind you; this is how I have used it (a lot) in the past, but I think it's still useful. — nitcion.

• It still doesn't make sense. You can claim ro cevni cu xamgu and pa cevni cu xamgu, and that does not mean that "only god is good", it in no way precludes that so'i gerku cu xamgu, for example. It means "The only god is good" (one god = all gods), but we want to say something else: "only god is good". — mi'e xorxes

• You're quite right. In weasely self-defense, what I was actually doing was ropamei le'i xamgu — nitcion.

• That works, but romei is enough. ropamei when there is only one, but 'only' can also be used with 'only two', 'only three', and so on. [Agreed — nitcion]

What does lo pa broda mean?

Fully expanded, su'o pa lo pa broda: at least one out of the one thing in the world which can be described (veridically) as the x1 of broda. Since brivla typically describe more than one thing, it's hard to find examples, so let's settle for lo pa cevni be le xebro. (There is not only one God for all religions, but there is only one God for that religion.)

And why is this unusable for "only"?

le pa gerku cu djuno
Only the dog knows.

• Where is the only there? That says that the one dog knows, it doesn't say anything about anyone else knowing or not. (The cat for example.)

Exactly which dog is specified by context.

Ah, but le pa (= ro le pa) is different to lo pa: le pa is the one thing you have in mind as being a gerku. I think this would be misleading as 'only', though, because it's implying that you're not thinking of any other dogs as being le gerku. I will not read this as 'only the dog', but as 'the one dog'. And I am not out of line to do so. Meta-Note: Using language is about being communicative first, and creative second. — nitcion.

lo pa djuno du le gerku

• cu du
• Yes, or even le gerku cu du ro djuno

le pa gerku poi djuno

le pa gerku poi djuno

i mo le pa gerku poi djuno

co'e

.i di'u .ue steci za'a la jbonai (Only in Lojbanistan...)

So what has "the one dog that knows" got to do with "only"?

Since we are in a logical language, consider what logic says: Only S are P is
All P are S. In the case above, {ro djuno cu du le gerku}. Other cases more intersting. pc >|8}