common sense says there's a God
If that were true, most people who believed would never question him.
You're here, aren't you
Yes, but you said "scientific evidence". There's no science or evidence in that statement.
The world is complex
Which doesn't mean a thing. Again, so science.
The Bible has been proven to be true because it mentions cities that actually existed. If the Bible was false, EVERY SINGLE city and person mentioned would be completely made up
If this were true, then most holy books of many religions would be true. Most, if not all mention places and people that can be proven through archaeology to have existed. However, since the bible has some places that exist in it, this does not mean that it can be proven true about metaphysical or supernatural things. And even if the bible is false about the supernatural, it doesn't mean that it's false archaeologically. How many fiction books mention real people, places, and events?
Faith is a reliable tool to determine truth. This is why 33 percent of the world is Christian
Faith isn't a reliable tool to prove anything. Faith is not based on reason or logic. And just because 33% of the world is professing christian (although this includes catholics and mormons, which this person probably wouldn't admit to being a "true christian (tm)"), doesn't mean a thing. Most people are gullible and stupid. They don't take any time to research and do the necessary study to learn things. They accept things based on not much more than emotional responses. Islam is the world's fastest growing religion, and at the rate it's going, it will take only about 25 years for it to overtake christianity, and become the world's largest religion. Does this mean it's the true religion? Not at all, although personally, I like Islam much more than I do christianity.