"It's plain that the same thing won't be willing at the same time to do or suffer opposites with respect to the same part and in relation to the same thing"-Socrates quoted in Plato's Republic (This is arguably the first refutation of relativism in logic)

Relativism operates as follows:

An idea is put forward. Bryan asserts that said idea may be true for others but is not true for him. Therefore Bryan is justified in rejecting the idea.

For this moral concept to be valid, it must be valid in real-world examples.

Cathy: "Look at this, Bryan. I read that people who don't strength-train tend to have weaker skeletal frames."
Bryan: "That may be true for you, but it is not true for me."

Cathy: "Your position results in a contradiction, so I can't accept it."
Bryan: "Contradictions may be bad on your ethnocentric, oppressive, dogmatic world view, but I don't think they are fallacious. Therefore my position is perfectly valid."

Furthermore, the relativist argument must be proven valid in order to be a valid conclusion, which presents a paradox, which is best summed up in this statement: "It is objectively true that there are no objective truths." In other words, it must be true that it is untrue, which is an untenable absurdity.

What's worse, if one allows the contradiction of relativism into a legal or moral equation; all following principals are subject to the principle of explosion, in which any number of formerly false assumptions become true. Posit an example within natural law, where the doctrine of non-coercion previously protected property from theft. When one arbitrarily injects relativism to allow, say, a state actor to confiscate private property, that former truth, that protection against non-coercion, breaks down so that other violations can follow. Property, after all, has the same logical value as life or liberty, for all come from the labors of the individual.

N.B: The author may have made a teleological assumption in the last paragraph, for the assumption that the individual has dignity assumes that dignity naturally came from somewhere.

This author appreciates the peer-review process.