[lojban-beginners] Re: Implications of partly negated, commutative logical connections

["Jorge Llambías" <jjllambias@gmail.com>]

On Wed, Jul 2, 2008 at 8:48 PM, namor <eldrikdo@gmail.com> wrote:
> Hi,
> I'm looking at:
> {mi nelci do .ijanai do prami mi} -- I like you if you love me.
>
> We should be able to swap the structure. So it's:
> {do prami mi .inaja mi nelci do} -- You love me only if I like you.
>
> These two structures - and therefore their translations - should be equal,
> but this is very very unintuitive to me.

Try:

It is true that I like you if it is true that you love me.

It is true that you love me only if it is true that I like you.


> The first structure sounds to me as if "your liking me" is a cause for "I like
> you".
> The second structure turns cause and effect upside down in my head.

Logical connectives say nothing about cause and effect. They only
tell you how the truth values of the two statements are related.
The connected statement will be true in these three cases:

  It is true that I like you and it is true that you love me.
  It is true that I like you and it is false that you love me.
  It is false that I like you and it is false that you love me.

and false when:

  It is false that I like you and it is true that you love me.

But there is no information given about what causes what, or indeed
whether any is caused by the other. English "if" does have causality
connotations, that's why it's not a very accurate translation of {ijanai}
or {inaja}.

> Did I make a mistake?
> If not, how to better translate the structures, so that the mean the same..?
>
> How to make clear what is cause and what is effect with logical connections?

To talk about causality, don't use logical connectives. For example:

mi nelci do .imu'ibo do prami mi
I like you because you love me.

da'i mi nelci do .iva'obo da'i do prami mi
I would like you if you would love me.

mu'o mi'e xorxes