VocabularyLiteratureEnglishing WritingAccents漢語

## Chapter 14: If Wishes Were Horses: The Lojban Connective System

### 12. Logical connection within tanru

As noted at the beginning of c14-§9, there is no logical connective in Lojban that joins selbri and nothing but selbri. However, it is possible to have logical connectives within a selbri, forming a kind of tanru that involves a logical connection. Consider the simple tanru “blanu zdani”, blue house. Now anything that is a blue ball, in the most ordinary understanding of the phrase at least, is both blue and a ball. And indeed, instead of “blanu bolci”, Lojbanists can say “blanu je bolci”, using a jek connective within the tanru. (We saw jeks used in c14-§11 also, but there they were always prefixed by “pe'e”; in this section they are used alone.) Here is a pair of examples:

```✥12.1    ti blanu zdani
This is-a-blue type-of house.

✥12.2 ti blanu je zdani
This is-blue and a-house.
```

But of course ✥12.1 and ✥12.2 are not necessarily equivalent in meaning! It is the most elementary point about Lojban tanru that ✥12.1 might just as well mean

```✥12.3    This is a house for blue inhabitants.
```

and ✥12.2 certainly is not equivalent in meaning to ✥12.3.

A full explanation of logical connection within tanru belongs rather to a discussion of selbri structure than to logical connectives in general. Why? Because although ✥12.2 happens to mean the same as

```✥12.4    ti blanu gi'e zdani
```

and therefore as

```✥12.5    ti blanu .ije ti zdani
```

the rule of expansion into separate bridi simply does not always work for tanru connection. Supposing Alice to be a person who lives in blue houses, then

```✥12.6    la .alis. cu blanu je zdani prenu
Alice is-a (blue and house) type-of-person.
```

would be true, because tanru grouping with a jek has higher precedence than unmarked tanru grouping, but:

```✥12.7    la .alis. cu blanu prenu
.ije la .alis. cu zdani prenu
Alice is-a blue person,
and Alice is-a house person.
```

is probably false, because the blueness is associated with the house, not with Alice, even leaving aside the question of what it means to say “Alice is a blue person”. (Perhaps she belongs to the Blue team, or is wearing blue clothes.) The semantic ambiguity of tanru make such logical manipulations impossible.

It suffices to note here, then, a few purely grammatical points about tanru logical connection. “bo” may be appended to jeks as to eks, with the same rules:

```✥12.8    la teris. cu ricfu je nakni jabo fetsi
Terry is rich and (male or female).
```

The components of tanru may be grouped with “ke” both before and after a logical connective:

```✥12.9    la .teris. cu [ke] ricfu ja pindi [ke'e]
je ke nakni ja fetsi [ke'e]
Terry is (rich or poor)
and (male or female).
```

where the first “ke … ke'e” pair may be omitted altogether by the rule of left-grouping, but is optionally permitted (as in bridi connection). In any case, both instances of “ke'e” may be elided.

The syntax of jeks is:

[na] [se] JA [nai]
parallel to eks and giheks.

Forethought tanru connection does not use geks, but uses guheks instead. Guheks have exactly the same form as geks:

[se] GUhA [nai]
Using guheks in tanru connection (rather than geks) resolves what would otherwise be an unacceptable ambiguity between bridi-tail and tanru connection:

```✥12.10  la .alis. gu'e ricfu gi fetsi
Alice is both rich and female.
```

Note that giks are used with guheks in exactly the same way they are used with geks. Like jeks, guheks bind more closely than unmarked tanru grouping does:

```✥12.11  la .alis. gu'e blanu gi zdani prenu
Alice is-a-(both blue and a-house) type-of-person.
```

is the forethought version of ✥12.6.

A word of caution about the use of logically connected tanru within descriptions. English-based intuition can lead the speaker astray. In correctly reducing

```✥12.12  mi viska pa nanmu .ije mi viska pa ninmu
I see a man, and I see a woman.
```

to

```✥12.13  mi viska pa nanmu .e pa ninmu
I see a man and a woman.
```

there is a great temptation to reduce further to:

```✥12.14  mi viska pa nanmu je ninmu
I see a man and woman.
```

But ✥12.14 means that you see one thing which is both a man and a woman simultaneously! A “nanmu je ninmu” is a manwoman, a presumably non-existent creature who is both a “nanmu” and a “ninmu”.