Answering Presuppositionalism: Basic
Theists who subscribe to the presuppositionalist school of thought say that atheists can't account for inductive reasoning. They claim that, in fact, whenever an atheist uses inductive reasoning, she is borrowing from the Christian worldview, because according to them, it's the only worldview that can account for the uniformity of nature, which is needed for inductive reasoning to work.
But even if the Christian is correct in his claim that an atheist can't account for a given facet of nature that she nevertheless depends upon, this is not that urgent deal-breaking problem that the presuppositionalist tends to paint for us.
Imagine a primitive society where most people believe that spirit ancestors reward the ritual act of watering a plant by causing that plant to grow. A person in this society who didn't believe in the existence of spirit ancestors would still go ahead and water his plants, because otherwise they would die.
The skeptics' peers might ask him, "How can you account for the fact that applying water causes the plant to grow in your worldview?" The skeptic, ignorant of plant biology, would have no answer. His peers might then say, "Every time you water your plants, you're borrowing from our worldview, because ours is the only system that can account for the connection between applying water to a plant and that plant's growth."
I hope the points I wanted to illustrate with this analogy are already clear, but I'll spell them out:
One, having an explanation does not make your position superior to that of those who may lack one.
Two, not being able to explain a phenomenon doesn't preclude you from legitimately assuming the reliability of that phenomenon.
Three, assuming the reliability of a phenomenon without being able to account for it does not mean that you implicitly accept the worldview of people claiming that theirs is the only explanation of that phenomenon.
Four, the failure of a person to explain a phenomenon doesn't invalidate their worldview or render it inconsistent.
Five, acknowledging that you don't have an answer is better than making things up.