If her argument is that you can't see electricity (simply to fill in the blank and a common retort) as a reason to accept Christianity as an answer to ignorance, then rational debate without a significant increase in basic scientific knowledge is out of order. You can, of course, take that approach; however, I have a very scientific way to address your dilemma.
You should both commit to a tour of all that Christianity has to offer. Seriously, be her guide in exploring all the different denominations. You have homework though. Your burden is learning the creeds of each before you attend to the extent that you are able to compare and contrast the denomination vs. the others, what the Bible actually says and what serious scholars consider regarding the differences.
You should both commit to a tour of all that Christianity has to offer. Seriously, be her guide in exploring all the different denominations. You have homework though. Your burden is learning the creeds of each before you attend to the extent that you are able to compare and contrast the denomination vs. the others, what the Bible actually says and what serious scholars consider regarding the differences.