Is There a Single Cause of a Chronic Disease?

i don't think there is such a thing as m s or rheumatod orthritus as a single thing, meaning that the same causal cascade happen for everybody. It's not even it's these three things that cause it, but it's some subside of these thousands of things that end up causing so many different diseases. So how to even think about the physiologic, causal aspects of it has to involve a more complex epistemology. Ray is a complex thing to figure out, which is why i think the best stuff that's happening in functional medicine is doing a better job.