[FOM] Why inclusive disjunction?

[Daniel C. Bastos]

On 1/10/07, mhebert <mhebert at aucegypt.edu> wrote:
>
> > Can anyone provide a principled reason for why logicians choose to
> > interpret "or" as inclusive disjunction?
> >
>
> Is it simply because (modern) logic was designed by mathematicians,
> and the inclusive or is more standard (or somehow more natural?) in
> mathematics, like in "a smaller or equal to b", and in the "union"
> (which includes the intersection)?

It seems to me that this example does not to illustrate your point. If a
and b are real numbers, and we say that a is smaller or equal to b, we
probably don't mean that both cases may occur. If we would, the
trichotomy law would contradict us. So isn't this an example where the
exclusive or is used?