Is truth relative?

A dialogue between Socrates and Protagoras)

Protagoras: Truth is relative. It is only a matter of opinion.

Socrates:

You mean that truth is mere subjective opinion?

Protagoras:

Exactly. What is true for you is true for you, and what is true for me, is true for me. Truth is subjective.

Socrates:

Do you really mean that? That my opinion is true by virtue of its being my opinion?

Protagoras:

Indeed I do.

Socrates:

My opinion is: Truth is absolute, not opinion, and that you, Mr. Protagoras, are absolutely in error. Since this is my opinion, then you must grant that it is true according to your philosophy.

Protagoras:

You are quite correct, Socrates.