Can Logic Exist Without Truth?

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The discussion revolves around a set of paradoxical statements that challenge the concepts of truth and falsehood. The first statement claims to be true, while the second asserts that the first is false, creating a contradiction. The third statement conditions its truth on the first being true, leading to further complications. Participants explore the implications of these statements, noting that if the first is true, the second must also be true, which contradicts the first. This creates a paradox reminiscent of the Liar Paradox, where statements refer to themselves in a way that leads to contradictions. Some argue that the third statement is true based on logical deductions, while others suggest it is meaningless due to the inherent contradictions in the first two statements. The conversation highlights the complexities of defining truth and the limitations of logic when faced with self-referential statements, ultimately questioning whether such statements can possess a definitive truth value.
  • #31
its true...
 
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  • #32
the answer is no

thats like saying: this statement is false.

its an infinitely self-contradicting paradox
 
  • #33
Final Hint:

When is a statement true?
 
  • #34
Sorry is this has already been posted by someone else:


Whatever the first statement is, it isn't true. For if it were true then it affirms that it is false. Therefor, statement 3 is a conditional in which the premise is not true. Therefor it is a true statement.
 
  • #35
It's a statement that can't be proven to be neither true nor false. This is Godel's incompleteness theorem, which states that in a consistant system, you can construct statements that can't be proved or refuted, thus resulting in a 'paradox'. It's just like the 'All what I'm saying is false' paradox.
 
  • #36
All assertions are false.

They refer to something
that does not exist.
 
  • #37
1. The following statement is true:
2. The previous statement is false.
3. If the first statement is true, then the second statement is false.
4. Is the third statement true or false?

'a' will be the proposition representing 1.
'b' for 2. etc...

Code:
1: a <-> b
2: b <-> ~a
3: c <-> (a > ~b)
-------------------
  assume b
  a from line 1
  ~a from line 2
  contradiction
therefore ~b
a from line 2
~a from line 1
contradiction

c (you can prove anything from contradictions, therefore c is true)
~c (you can prove anything from contradictions, therefore ~c is true)
 
  • #38
Look carefull at the third statement:

IF TRUE
"If the first statement is true, then the second statement is false."

IF FALSE
"If the first statement is true, then the second statement is NOT false."

Now you should be able to see that the third statement is not definied, when the first statement is not true. But the tricky part is that you can't determine whether or not the first statement is true:

if 1. is true => 2. must be true => 1. must be false => 2. must be false => 1. must be true => and then we are back at square one...

Since the first and second statement results in an infinitive loop, we have a paradox; their exits no such solution!
 
  • #39
Logic requires that the originating premise be true. Now this opens up
a Pandora's box in itself-more later. A paradox is simply a
contradicting statement but this is not the whole picture. The original
statement invades our perception of logic completely. Everything you and I take for granted is based on our "knowledge" of true facts.

Therefore, when we argue with each other, we start with what we assume
is a known fact. We call them facts because together you and I take them to be true. The method by which we imply truths is called logic.

But lest we forget, it is all based on facts or truths. If we start with something that turns out not to be a fact, then the whole concept breaks down.

The opposite implication is that there may be hidden facts. In other words, what we all take to be for granted as being false, might actually be true. When NASA looks at problems, they categorize them into one of four categories:

a) Known knowns
b) Unknown knowns
c) Known unknowns and
d) unknown unknowns

All very logical, right? Well, where the system breaks down is when the problem doesn't fit our capability to reason-it doesn't fit in the box.

Our problem doesn't fit the box because it is illogical. This is where logic breaks down-when something is not logical. But be careful with categorizing your thinking because what may not be logical to us is not necessarily illogical in truth. When you say something is illogical, you are really saying it doesn't make sense to me.

Now since logic is devolved from the concept of truth, philosophers in the past have argued over whether it actually exists absolutely or not.

Or is truth just a concept that is man-made? Is your truth the same as my truth? Do we even know what truth is? Do you believe in truth?
 

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