Can Logic Exist Without Truth?

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Discussion Overview

The discussion revolves around the nature of truth in logical statements, particularly focusing on a set of paradoxical statements that resemble the Liar Paradox. Participants explore whether logic can exist without truth and how the statements interact with each other in terms of truth values. The scope includes theoretical reasoning, paradox exploration, and logical implications.

Discussion Character

  • Exploratory
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Some participants assert that the first statement cannot be true, leading to the conclusion that the third statement is true.
  • Others argue that the third statement is false due to contradictions arising from the first two statements.
  • A few participants suggest that the statements create a paradox, making it difficult to assign a truth value to the third statement.
  • Some propose that if one allows for partial truths, the third statement could be considered true.
  • Several participants express uncertainty about the truth values of the statements, indicating that they do not correlate with each other.
  • One participant likens the problem to a scenario involving two people making contradictory statements, suggesting that this reflects the nature of the paradox.
  • Another participant notes that the third statement is a meta statement and references Lewis Carroll's work as a related example.
  • Some participants emphasize the need for clear definitions of "true" and "false" to avoid ambiguity in the discussion.

Areas of Agreement / Disagreement

Participants do not reach a consensus; multiple competing views remain regarding the truth value of the third statement, with some asserting it is true, others claiming it is false, and some suggesting it is neither true nor false.

Contextual Notes

The discussion highlights limitations in the definitions of truth and falsehood, as well as the implications of accepting paradoxical statements. There are unresolved mathematical steps and assumptions regarding the nature of the statements and their interrelations.

  • #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 consistent 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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