Why "mysterious ways" don't matter.

[Esquilax]

The problem is in your last sentence: a knowing subject only ever has belief that he knows something. The level of certainty that the subject possesses about a given object does not affect whether or not that object truly exists. You can know something for absolute certain and still be dead wrong. Which is the point I'm making: if objective moral values collapse without god around, then they were never objectively real, they were merely thoughts in his head, and hence subjective.

Wouldn't this naturally lead one to fideism?

Not necessarily: you have a higher degree of accuracy for your beliefs when they are subjected to reason and evidence than through faith. It's just that a claim of knowledge doesn't automatically entail the truth of that claim, nor does an objectively extant thing require a knowledge claim to exist.

I think the issue here is that Chad is talking about knowledge of objective morality, whereas I'm talking about the existence of it. I agree with him that knowledge requires both a subject and a mind to host that knowledge claim, but when we're talking about something that apparently blinks out of existence the moment a certain mind disappears, we're talking about an opinion and not a referent to something that actually exists.