This is a question that I hear from time to time. Here is a very interesting response to that question:
If all truth is relative, then the statement “All truth is relative” would be absolutely true. If it is absolutely true, then not all things are relative and the statement that “All truth is relative” is false.
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January 8th, 2007 at 9:20 pm
If all truth is relative, then the truth of the statement, ‘All truth is relative’, is also conditional, not absolute.