> Interesting, so when you can't subject something to the empirical observation... such as the original creation of the sun, where exactly does one gain a sure confidence in the explanation for it's original cause?
Causality, as such, is not directly observable. Correlation is, and causation is inferred from patterns of correlation.
When done scientifically, the specific method to go from observed correlation to conclusions about causation is to form a hypothesis, predict future observations based on that hypothesis that could be falsified to disprove it, and then go and test those predictions.
Eventually, doing this enough, and you'll end up with falsifiable models that have been rigorously tested from which you can make inferences about what must have caused events where you cannot observe the correlated event that you would infer to be the cause that are as strong as the inferences of causation you can make with events where you observe both the putative cause and the effect for which you infer it is the cause.
> If you haven't observed the cause, you have no rational reason to establish 100% confidence about what it was.
If you have observed the supposed cause -- and its supposed effect -- you have no rational reason to assert a causal link with actual 100% certainty. OTOH, with sufficient related observations, prediction, and testing those predictions, you can construct a model of causality that lets you get arbitrarily close to 100% certainty in stating what the cause of an observed effect is, whether or not you can observe the event that is the inferred cause.
> This is really simple rational thinking
It is simply incorrect, and seems grounded in both a mistake about what science does and the mistaken belief that causality is directly observable.
> I don't get how science arrives at any level of confidence about causes that it can't (nor has ever) observed.
The same way it arrives at any level of confidence about causes that it can observe (observe the event, that is, not the fact that it is a "cause", which is never observable, only inferable.)
> I have no problem with confidence in what it can observe, I take issue when it can't observe and attempts to take what it can observe and confidently extrapolate that into the past.
The whole thing science does is produce and refine methods of inferring things that are not observed from things that are.