First of all, I want to point out I am not any expert in philosophy, so this question is not based in no further readings, but only my own knowledge in logic.
Imagine I want to proof the truth is relative and that will lead to a contradiction:
- Premise: The truth is relative.
- Deduction: If the truth is relative, there are neither pure true nor false statements.
- Demonstration: Therefore, to affirm that the truth is absolute is neither true nor false, therefore, it can be affirmed that the truth is absolute, contradicting the premise.
- Conclusion: Therefore, the truth must be absolute.
Now, imagine I want to proof the truth is absolute and that will not lead to any contradiction:
- Premise: The truth is absolute.
- Deduction: If the truth is absolute, there are pure true and false statements.
- Demonstration: Therefore, to affirm that the truth is relative is true or false, but, now it cannot be affirmed that the truth is relative, because it is purely false (if it was true, we would be accepting relativity in the premise, which we do not). And if we say truth is absolute, that is the premise.
- Conclusion: Therefore, the truth IS absolute (which does not lead to any contradiction).
What is it wrong in my proof? I am sure there must be lots of ideas I am missing.
(Note that my sense of relativity does not refer to a disparity of opinions that may exist in politics, but, for example, truths regarding the universe; in the sense, for example, of Ayn Rand's absolute truth as opposed to relative truths of other classical philosophers).