axiom a3 is missing parentheses around it
On Sun, Aug 13, 2023 at 5:30 PM Jeroen van Rensen
wrote:
> Hello everyone,
>
> I am trying to prove the following statement:
>
> ! ! p |- p
>
> The formal proof is as follows (the axioms are the same as in set.mm):
>
> 1. ! ! p (Premiss)
> 2. ! ! p ->
Hello everyone,
I am trying to prove the following statement:
! ! p |- p
The formal proof is as follows (the axioms are the same as in set.mm):
1. ! ! p (Premiss)
2. ! ! p -> (! ! ! ! p -> ! ! p) (Axiom 1)
3. ! ! ! ! p -> ! ! p (MP 1, 2)
4. (! ! ! ! p -> ! ! p) -> (! p -> ! ! ! p) (Axiom 3)
5.
