Invitation for Atheists to Debate a Christian via Skype

[Belacqua]

Christians only ever argue for the existence of a first cause and they never explain why that first cause is supposedly intelligent. Unless you include them attacking evolution (as they have no argument for intelligent design now that we know evolution is true, and evolution can explain the world, so they have to attack evolution).  And they never say why it should be the specifically Christian God. Unless you include them insisting that there is historical evidence for the resurrection. But evolution is true, there is no historical evidence of Jesus's resurrection at all, and a first cause is just a first cause. They can call it a prime mover all they want ... it doesn't make it anything other than just a first cause.

Nothing in modern physics demands a cause for all phenomena; the spontaneous transition of an electron to a lower or ground state isn't caused by anything; it just happens.  Ditto for radioactive decay of an unstable atom into its daughter elements.

Radioactive decay or the transition of an electron as something causeless does argue against temporal First Cause arguments like the so-called Kalam argument. 

We should keep in mind, though, that Aristotle and Aquinas specifically rejected such temporal arguments. When they speak of a first cause, it isn't an event which brings about another event. So the examples you give from physics don't touch the traditional First Cause arguments. 

Both of the occurrences you mention do rely on causes in the sense that Aristotle uses the word: conditions of the world which must exist for their dependent conditions to exist. The existence of an unstable atom and its decay depend on the essentially prior existence of space-time and the laws of physics. If space-time and the laws of physics went away, so would such atoms. This is the kind of cause which both Aristotle and Aquinas refer to. 

As an analogy, we could say that temporal causal arguments say that the pool ball went into the pocket because another ball hit it, and that ball hit it because the pool cue hit it, and the pool cue hit it because the pool player aimed it, etc., in a temporal chain of actions. An essential causal chain, on the other hand, would say that the ball went into the pocket (in part) because of the existence of the pocket, and of the pool table, and of the laws of motion, and of space-time, and of all the other things that must be the case if the ball is to do that. Some of these might be temporally prior, but that's not the important thing. Some of them are probably simultaneous, as neither space-time nor the laws of motion are likely to have existed one before the other. 

Granted, most Christians on the Internet argue the easier, temporal version, and don't understand Aquinas. 

And as SenseMaker says, very sensibly, anyone arguing that such a First Cause argument points to a specifically Christian God needs a whole lot of further arguing.