why is if ganai..gi?

["G. Dyke" <gordon.dyke@bluewin.ch>]

I'm still following this logic course.

we are still doing propositional logic, using the following axioms (among
others and using G for Gamma (hypothesis), - for not, | to separate
judgments from hypothesesesesesse ahemm and F for false):

G, A | F  ||  G | -A         J red absurd.
G,-A | F  ||  G | A          K red absurd.

The lecturer explained that "intuitive" logicians preferred not to accept
the K red absurd. as it is used to demonstrate:

|| G | A or -A               exclusion of a third case

He also explained that sometimes this third case exclusion is taken as an
axiom (which is also rejected by many).

I seem to be getting cause and consequence of being "intuitive" mixed up
here, but anyways:

>From the refgramm, it seems to be accepted that a proposition is either true
or false.

But why force this into lojban:

A => B <=> -B or A

when this judgment can only be made given K red. or third case exclusion.

Greg, hoping he got it right and didn't make too much of a fool of himself.
--
http://www.myepfl.ch/gregory.dyke

.i lo'e to'e makcu cu djica lenu tolcumla morsi kei lo telda'a
.i lo'e je'a makcu cu go'i to'ebo le se go'i