How to beat a presupp at their own game

[GUBU]

So I had a debate with a Christian presuppositionalist and I don't think I did particularly well. I haven't debated Christians in a while so I'm pretty rusty, but they were trying to poke holes in my naturalistic framework.

He kept insisting that because I don't KNOW everything about gravity that there is nothing in my system that would prevent gravity from operating differently tomorrow. Just because gravity has observable patterns today or yesterday doesn't mean it will be consistent tomorrow or the next, so in my worldview anything can change. What regulates gravity or the laws of physics? What is the absolute etc - so I naturally said that I don't know.

His point was that God is the ground of all things yadda yadda - so I told him that just because I don't know EVERYTHING doesn't mean I don't know ANYTHING, and he, funnily enough said the opposite. Theists.

I seriously need to learn how to deconstruct these theist arguments because I am so weak right now - he then went to Modus Pollens, which I've never even heard of. When asking for evidence for God, he says that God has revealed himself to everyone but as an atheist that I have suppressed the knowledge. No I haven't. That is the Christian line of reasoning - that I just don't WANT there to be a God.

I need to learn how to defend my beliefs.

He's wrong. Scientific theories don't control phenomena, they describe them. We change scientific theories not because we are changing phenomena but because we are finding moreaccurate ways to describe them. Gravity didn't change when we switched from Newtonian equations to Einstein's relativity, just our understanding of it.

In actual fact, your interlocutor describes in his god centric system exactly the kind of gravity changing system he derides. If god controls gravity, what is there to stop him from deciding, on a whim, to reverse its effects in the morning?