Archimedes (287–212 B.C.), the Greek mathematician and physicist who yelled “Eureka!” as he ran naked from his bathtub at the discovery of the principle of displacement (Archimedes’ Principle), once boasted that given the proper lever, and given a place to stand, he could “move the earth.” But upon what would Archimedes stand to accomplish such a feat? Certainly not on the earth itself. Archimedes needed a place to stand outside the earth, a place different from the earth he wanted to move. Of course, his lever needed a fulcrum. This, too, had to rest on something.
Atlas of Greek Mythology (son of Titan and brother of Prometheus), had a similar problem. Atlas was condemned by Zeus to stand eternally at the western end of the earth to hold up the sky. In art, however, Atlas is depicted as holding up the world. But what is Atlas using for his support of the earth? What is he standing upon?
All argumentation will inevitably be taken back to a single reference point from which the arguer will appeal for authority to support his worldview. That reference point, for example, might be the expert opinion of others. Of course, these experts are not the ultimate authorities. They also appeal to some decisive standard. “[J]ust because most of the authorities in a field are shouting in unison that they know the truth, it ain’t necessarily so.” It is upon a final standard—a standard to which no greater appeal is made—that all worldviews rest.
At the center of every world-view is what might be called the “touchstone proposition” of that world-view, a proposition that is held to be the fundamental truth about reality and serves as a criterion to determine which other propositions may or may not count as candidates for belief.
The idea of a touchstone to establish authenticity, fineness, right and wrong, and justice is an old one. “In the days of the gold rush men used a touchstone, a fine grained dark stone, such as jasper, to determine the quality of the gold which they had discovered. Today a Geiger counter is used to locate uranium and other precious metals. In baseball the umpire makes the decisions in the contest between the pitcher and the batter. In the courtroom the judge decides questions of law. In their respective fields the touchstone, the Geiger counter, the umpire and the judge speak with authority.”
Nothing has changed in our day of philosophical and political debates. There is an underlying starting point for argumentation. The goal in apologetics is to find that oppositional starting point and force the arguer to live consistently with its underlying assumptions. In a radio interview I did on Crosstalk last week, a homosexual man called in and stated that he and his new “husband” were very happy in their “marital” relationship. I asked him where he got the idea of marriage. Of course, he got it from the Bible. He wanted some of the things the Bible advocates (marriage) but not others (prohibitions against homosexual behavior). Then there is the problem with his use of “happiness” to justify a homosexual relationship. There are people out there who believe that robbing banks makes them happy. Why is one person’s brand of happiness ethically justified while another is not? Forcing the antithesis means forcing someone to account for the basis of his worldview. It might not be polite, but it’s the only methodology that is biblical.
 William R. Fix, The Bone Peddlers: Selling Evolution (New York: Macmillan, 1984), xix.
 William H. Halverson, A Concise Introduction to Philosophy, 3rd ed. (New York: Random House, 1976), 384. Quoted in Ronald H. Nash, Faith and Reason: Searching for a Rational Faith (Grand Rapids, MI: Zondervan/Academie, 1988), 46.
 George M. Marston, The Voice of Authority (Nutley, NJ: Presbyterian and Reformed, 1960), xv.