The question ‘Who made God?’ crops up in a probability argument presented by Richard Dawkins in The God Delusion.
And here we must begin with a lengthy note of caution. Probability arguments are often used in debates relating to God, science, creation and evolution, but they are almost always used naively. Probability theory is a branch of mathematics, concerned initially with discrete numbers (like the probability of getting heads or tails when you toss a coin), but extending also to continuous ‘distribution functions’ (like a curve showing people’s average income plotted against their age). Either way, it’s all mathematics. The theory can, of course, be applied to the real world as in the examples given, but there is nothing of the real world built into the theory itself.
For example, its coin-tossing calculations take no account of the possibility that the coin might land on its edge and get stuck in that position — something that could happen quite often if you’re tossing the coin on a soft sandy beach.