Wait, wait, wait. Mr Atheist has redeemed himself with a quote I might just steal “God plus the universe looks indistinguishable from a universe without God at all.”
Okay, so our Christian claims there are two types of cause: event causes and agent causes. One of these is the domain of physics, where the other is freewill. To steal the example from the book (because I was going to use a meteorological example to use some thinking from my degree for once) if you hear a water pipe knocking you can either conclude that the cause is hot water or a person hitting it. If it is hot water, and you want to fully understand the situation, you want to know why the hot water has turned on and that will lead you to a timer. Understanding the timer will take you to its programming (I’ve deviated from the given example now) and, if you still want to understand, the programming will lead you to a programmer; that is why the hot water is on now. If it is a person hitting those pipes, then a person is hitting them. End of.
Except it’s not end of at all. You can’t take causal chains back to an agent cause, drop off the line of questioning, and consider it done. That doesn’t make sense at all. Is the question ‘Why did you do that?’ outright absurd? Why is someone hitting the pipes? Are they bored? Why are they bored? Why did the programmer program the boiler to come on at 4:30pm? So the water is hot for 5pm. Why does water take half an hour to heat up? The specific heat capacity of water. Why is 5pm a good time for hot water? All the things a causal agent does have influences. These influences are causes. The chain of inquiry does not stop at a conscious agent with will.
This chapter is rife with issues; neither writer understands the implications of there being no time and no before and no T-1. The best explanation is still that the philosophical nothing that religious philosophers and apologists demand must have existed actually didn’t, and the nothing that did exist is the Kraussian nothing that is unstable. But the best answer, still, as the atheist points out, is ‘I dunno’. It was the right answer before heliocentricism, it was the right answer before evolution, it was right before Newton’s theories of motion, and it was right before plate tectonics. And it’s right now.