But if you don't believe in God, who do you think made you?

Q: But if you don't believe in God, who do you think made you?

A: Sometimes, when a man and a woman are very much in love, they ... no, wait, wrong lecture.

Seriously, most atheists would answer this question with "My parents." And that would be it. They do not believe that an almighty Creator was involved in any way, just regular old people doing that regular old thing. A god is as unnecessary to explain human conception as it is to explain the conception of weasels.

But just because an atheist is someone who lacks God-belief doesn't mean that all atheists believe in metaphysical naturalism (the idea that the physical, natural world is all there is). For instance, a Buddhist atheist might believe that there is a non-material component to all life, which we are unable to measure through our normal senses, but which accrues various amounts of karmic debt. This insubstantial essence lives on beyond us, and in fact incorporates itself into future iterations of the self. In that sense, such a person might reply "My parents, me, and the karmic nature of the universe."

Most atheists, however, would likely consider this sort of non-divine supernaturalism as claptrap and nonsense. By far the most common answer is that we are created by the same mindless forces of nature responsible for every other living non-human creature we have ever seen.

Aren't science and atheism the same thing?

Q: Aren't science and atheism the same thing?

A: No, science and atheism are two completely different things. Someone can be a scientist and be an atheist or a theist of any sort. There are Christian scientists, Hindu scientists, Muslim scientists, atheist scientists. Science doesn't say anything one way or another about metaphysical issues (subjects having to do with the supernatural, or ideas that are not based in a physical universe); it is concerned solely and exclusively with that which is natural.

Most atheists subscribe to metaphysical naturalism, the idea that the natural world is all there is, period. Scientists subscribe to methodological naturalism, the idea that when trying to figure out how things work, only natural phenomena should be considered. Conflating the two is an error. One can be a scientist, employing methodological naturalism to figure out why volcanoes erupt (weak spots in the mantle allow deep magma to surge to the surface, not "Baal is angry with us") while being, say, a Christian (God created the world such that the mantle has weak spots in it that allow magma to surge to the surface). The two are similar, but different, and conflating the proponents of one with the proponents of the other is a mistake.

Implying that science is the same thing as atheism is like saying "Muslims believe lightning is a natural force, not bolts from an angry god. Science also believes lightning is a natural force, not bolts from an angry god, therefore science is Muslim in nature." Or put another way, it's the error of thinking that because set A and set B have subset C in common, set A equals set B.