We are talking about this:
Then you claimed ~A is the negation of A
Let's use OR.
In
http://www.internationalskeptics.com/forums/showpost.php?p=11359187&postcount=1901 ~A is defined such that
no options are defined.
In that case A OR ~A ---> T (tautology) since A,~A are not simultaneously taken.
Now let's define ~A by
the claims about the
defined options.
In case of OR, It is T to claim that the two
defined options are not simultaneously taken (written as T(for one option) OR T(for the other option) --> T(for not simultaneously be taken)) and since they are not simultaneously taken, indeed A OR ~A ---> T (tautology) exactly as claimed about the
defined options by T OR T --> T.
Also let's correct what was written about the
claims about the
defined options in case of A OR ~A truth table:
By using OR logical connective between the
defined options, the truth table is as follows:
It is ~T to claim that no one of the
defined options is possible (written as ~T OR ~T --> ~T)
It is T to claim that at least one of the
defined options is possible (written as T OR ~T --> T, ~T OR T --> T)
It is T to claim that the two
defined options are not simultaneously taken (written as T OR T --> T)
So the truth table of A OR ~A is:
Code:
A OR ~A
--------
~T ~T --> ~T
~T T --> T
T ~T --> T
T T --> T
OR logical connective guarantees that the two
defined options are not simultaneously taken, so the contradiction avoided (A OR ~A --> T (tautology)).