10.20. Logical and non-logical connections between tenses

Like many things in Lojban, tenses may be logically connected; logical connection is explained in more detail in Chapter 14 . Some of the terminology in this section will be clear only if you already understand logical connectives.

The appropriate logical connectives belong to selma'o JA. A logical connective between tenses can always be expanded to one between sentences:

Example 10.152.

mi	pu	je	ba	klama	le	zarci
I	[past]	and	[future]	go-to	the	market.

I went and will go to the market.

means the same as:

Example 10.153.

mi	pu	klama	le	zarci
I	[past]	go-to	the	market.

.ije	mi	ba	klama	le	zarci
And	I	[future]	go-to	the	market.

I went to the market, and I will go to the market.

Tense connection and tense negation are combined in:

Example 10.154.

mi	punai	je	canai	je	ba	klama	le	zarci
I	[past-not]	and	[present-not]	and	[future]	go-to	the	market.

I haven't yet gone to the market, but I will in future.

Example 10.154 is far more specific than

Example 10.155.

mi	ba	klama	le	zarci
I	[future]	go-to	the	market.

which only says that I will go, without claiming anything about my past or present. ba does not imply punai or canai ; to compel that interpretation, either a logical connection or a ZAhO is needed.

Tense negation can often be removed in favor of negation in the logical connective itself. The following examples are equivalent in meaning:

Example 10.156.

mi	mo'izu'anai	je	mo'iri'u	cadzu
I	[motion-left-not]	and	[motion-right]	walk.

I walk not leftward but rightward.

Example 10.157.

mi	mo'izu'a	naje	mo'iri'u	cadzu
I	[motion-left]	not-and	[motion-right]	walk.

I walk not leftward but rightward.

There are no forethought logical connections between tenses allowed by the grammar, to keep tenses simpler. Nor is there any way to override simple left-grouping of the connectives, the Lojban default.

The non-logical connectives of selma'o JOI, BIhI, and GAhO are also permitted between tenses. One application is to specify intervals not by size, but by their end-points ( bi'o belongs to selma'o BIhI, and connects the end-points of an ordered interval, like English “from ... to” ):

Example 10.158.

mi	puza	bi'o	bazu	vasxu
I	[past-medium]	from…to	[future-long]	breathe.

I breathe from a medium time ago till a long time to come.

(It is to be hoped that I have a long life ahead of me.)

One additional use of non-logical connectives within tenses is discussed in Section 10.21 . Other uses will probably be identified in future.