Truth and Actions

You're right in saying that your friend is engaged in a kind of contradiction. Of course "forcing your beliefs" is a rhetorical expression. We live in a relatively free country, where nobody has a right to try to literally force beliefs on anyone else. When people use that expression, they usually mean that someone believes his view is true and is trying to persuade another person to believe the same thing. That, of course, is not "forcing," except by way of a bad metaphor. If someone thinks that attempting to persuade constitutes force, then he is evidently a relativist of the worst sort. And of course that sort of relativism is contradictory when the relativist tries to persuade someone else that relativism is true.

Of course, some relativists are so extreme in their relativism that they don't care whether they persuade anyone or not. In that case, it's best not to argue with them. But we can still witness by our life and our love.

It's true that a person's inconsistency doesn't affect the truth or falsity of what the person believes. However, when someone is inconsistent, that detracts from the credibility of the person's arguments. His view might still be true, but he is unable to persuade anyone else.

So atheism might still be true, even if atheists are inconsistent. But the inconsistent atheist has failed to make his position credible.

One of the rules of rational debate is that the parties avoid inconsistency. If one is inconsistent, he has opted out of the game. He is no longer engaged in rational debate. That's OK. We don't have to play that game. We can relate to one another in other ways. But it's important that people know that inconsistency violates the rules of rational debate.

And it's also important to know that if atheism is a necessarily inconsistent position, it is untrue. So an alternative must be true. Van Til's claim is that the only coherent alternative is Christian theism.