From sumti to abstraction: tu'a

When looking up words in a gismu list, you may have already noticed that, where languages like English have people or things as subjects and objects, Lojban often uses abstractions instead as gismu places. For example, in English, you say that someone is interesting, or something is interesting. In Lojban, you aren't really meant to say either. The definition of cinri is:

x1 (abstraction) interests/is interesting to x2; x2 is interested in x1

In other words, as far as Lojban is concerned, it's not things or people that are interesting, but actions or properties involving those things or people. For example, Jyoti cannot be said to be interesting simply by virtue of being Jyoti; the way Lojban puts it, it's the things Jyoti does (or is) that are interesting — the way she talks about British sitcoms, her choice of headgear, her tendency to break into '80s songs after she's had a few drinks. (Oh, I forgot to tell you about all that. Maybe next course.)

The same goes for fenki 'crazy'. In almost every language, it is people that are called crazy. Only occasionally are actions also called crazy. Lojban, however, defines fenki as:

x1 (action/event) is crazy/insane/mad/frantic/in a frenzy (one sense) by standard x2

In other words, as far as Lojban is concerned, craziness lies in actions, not in people; a crazy person is by definition someone who does crazy actions.

Note: This means that someone suffering from the particular forms of mental illness loosely called 'crazy' wouldn't be called fenki in Lojban — since their condition is not primarily a matter of socially unaceptable actions — but rather menli bilma: 'mentally ill'.

For now, you may be prepared to accept this as an endearing quirk of Lojban. (If you're not, we explain why Lojban is all topsy-turvy like this in the next section.) But very often, you have no idea what to say is the selbri of that abstraction, or you don't particularly care to. For example, yes, Jyoti doing this, that and the other is what is interesting about her; but I may not know first-hand what exactly her particular talents are, or I may not feel like going into a five-minute spiel every time I merely want to point out that she is interesting. If I can't say the Lojban for "Jyoti is interesting", I should at least be able to say something like "Jyoti {doing some stuff I'm not listing here} is interesting", or "Some things about Jyoti are interesting." In other words, I have to say

lenu la djiotis. cu ___ cu cinri

but I shouldn't have to fill in that slot with an explicit selbri each time.

There are slots in Lojban sentences that we have in fact been leaving empty all the time. Remember zo'e? zo'e is the 'don't care' value we leave implied in the unspecified places of bridi. For example, when I say mi klama le barja, I'm not bothering to specify my point of origin, route, or vehicle. They are all implied to be zo'e: mi klama le barja zo'e zo'e zo'e. This means that there is a point of origin, a route and a vehicle involved, but we don't really care what they are.

zo'e is a sumti; but it has a selbri equivalent, co'e. co'e can appear where any selbri can appear, but it leaves the relationship between its sumti unspecified. So mi co'e le barja means something like "I thingummy the bar": the bar and I are in some relationship, but I'm not bothering to say what it is. I might be going to it, coming from it, sleeping in it, refurbishing it, or hearing about my neighbour getting drunk in it once. It just doesn't matter enough for me to say what.

Now normally, you can't get away with this: if you leave out the selbri in your story, you pretty much have no story. But with these abstractions that we wish weren't really abstractions, co'e is just what you need: you can get away with making an abstraction containing only the sumti you want to talk about. You don't have to specify anything else in the abstraction — especially not the selbri. So if I want to say "Jyoti is interesting", I need only say

lenu la djiotis. cu co'e cu cinri

I'm still saying an abstraction involving Jyoti is what is interesting, so I'm following the requirements of the gismu list. But that's all I'm saying; what particular abstraction it is that is interesting, I am leaving entirely open. In the same way, if I want to say "Zhang is crazy" (or "berserk", probably a closer translation of fenki), I don't have to enumerate the various wacky stunts he has pulled over the years. I can simply say that "some stuff about Zhang is crazy", which in Lojban comes out as

lenu la jan. co'e cu fenki

The value of co'e could be

or whatever; we're just not bothering to name it here.

Lojban can go one better, though. As you can tell, Lojban is going to have you saying lenu ___ cu co'e kei quite often (and you never know when you might need that kei terminator); so it offers you an abbreviation: tu'a. tu'a da means lesu'u da cu co'e kei (where su'u, you may recall, is the generic abstractor); so you can translate tu'a as "some abstraction associated with...", or more colloquially, "some stuff about...". tu'a is easily the most popular way of dealing with abstractions you wish weren't there in Lojban; Lojban sentences using it come out fairly similar to the natural language sentences without abstractions that we're used to seeing. So the usual Lojban for "Jyoti is interesting" is

tu'a la djiotis. cinri

and the usual Lojban for "Zhang is crazy" is

tu'a la jan. fenki



x1 desires/wants/wishes x2 (event/state) for purpose x3


x1 [state/event/process] commences/initiates/starts/begins to occur; (intransitive verb)


x1 (event) annoys/irritates/bothers/distracts x2


x1 is fond of/likes/has a taste for x2 (object/state)


x1 (event/state) is an accident/unintentional on the part of x2; x1 is an accident


x1 tries/attempts/makes an effort to do/attain x2 (event/state/property) by actions/method x3

Exercise 3

Some of these sentences need to be translated in Lojban with tu'a, and some don't. Supply the appropriate translation, in either case.

  1. I tried the curry.

  2. I wanted the curry.

  3. I liked the curry.

  4. My leaving was accidental.

  5. Gratitude annoys me.

  6. Curry annoys me.

  7. The irritation has begun.