[lojban-beginners] Re: Number questions

[Jorge Llambías <jjllambias@gmail.com>]

On 8/10/05, Hal Fulton <hal9000@hypermetrics.com> wrote:
> This appears in _Lojban for Beginners_:
> 
>    li ci su'i vo du li xo
>    3 + 4 = ?
> 
> Fine, but I have some questions:
> 
>   - Why no "li" on "vo"? Is it optional or not?
>   - Why "li" on "xo"? Optional or not? If optional,
>     does meaning change?
>   - If we can put "li" on "xo", can we put "le" on "ma"?
>       do nelci le ma
>     Optional or not? If optional, does meaning change?

No, they are not optional.

{du} is a selbri, which takes sumti as its arguments.
In this case {li ci su'i vo} and {li xo} are the two 
arguments of {du}. {xo} by itself is not a sumti, so it 
cannot be an argument of the selbri {du}.

{li} converts a mathematical expression into a sumti.
{xo} and {ci su'i vo} are mathematical expressions.
To use them as arguments of {du}, you need to put 
a {li} in front to convert them into sumti.

{ci}, {vo} and {xo} are simple operands. An operand is 
the simplest kind of mathematical expression.
{su'i} is an operator. An operator joins two operands
into a complex mathematical expression, so 
{ci su'i vo} is a complex mathematical expression.
{ci su'i vo} could function in turn as an operand for 
another operator, for example {(ci su'i vo) su'i (mu)}.

The internal grammar of mathematical expressions 
(MEX) is in some respects similar to the grammar 
of predicates, but not really equivalent. {ma} is a sumti 
by itself and does not take a gadri. {mo}, on the other 
hand, is a selbri, and so {le mo} is a sumti. 
{do nelci le mo} is correct.

mu'o mi'e xorxes