If set M which does not contain itself contain[s] itself, set M is not set
M. If set M which does not contain itself does not contain itself, then set
M is set M. So If set M contains M, set M is not element of set M, and then
if set M does not contain M, set M is element of set M. This means that Set
M is composed of two dual implications between contradictory propositions.
Let p= "M is not element of M".If not p, then p, and, if p, then not p.
then p Ěnot p.
Because this set M is contradictory to the true statement and the false
statement, and has to be expressed by a dual implication between two
contradictory statements, this set M is assigned the third truth value
which is contradictory to "the true" or "the false". There might not be
comprehensible proposition as an example of the proposition with the third
truth value any further.
The third truth value is, at times, assigned to a possible proposition, and
at times, assigned to a recurrent propositions, and at times, assigned to a
moral proposition which has the political contents, and above all, assigned
to a paradoxical propositions. And, such a phenomenon overflows in the
world. The third truth value represents these paradoxical or reflexive or
recurrent or possible propositions which contain itself anywhere or
anything in it's propositions.
Let p a possible proposition, p depend on q which is something immature or
future, but something q depend on a possible proposition p.
Now, let {p=p(q)} p depend on q, then p=p(q) and q=q(p). So,
p=p(q(p(q.......... .
Let q=-p. Then, p=p(-p(p(-p(p(-p...... .
This is the symbolic expression of a possible proposition p and its dual
implication.
The statement of this symbolic expression are a possible proposition or a
recurrent proposition or a future proposition or moral proposition, etc. So
this type of proposition is natural events in our life.
Note: Denial of this third valued proposition
As these third valued propositions exist certainly, the denial of the third
valued proposition becomes logical problem. So this four valued logic
assumes this negative form of the third truth value to the fourth truth
value. Then, this four valued logic is able to have the law of
contradiction or excluded middles like 2-valued logic. This is the reason
that this logic is said the simplest expansion of 2-valued logic.
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copied verbatim from http://www.elix.com/txQA5678.htm
I first read about this in Bart Kosko's (http://sipi.usc.edu/~kosko/)
"Fuzzy Thinking".
Dissipating some chaos,
Magos
The sentence below is true.
The sentence above is false.