So basically all of these systems are intimately interconnected, and probably before this is done with researchers will find five more systems intimately interconnected with all of these. It might be that inflammation is the master system which causes a cascade of events in all of the others. It might be that one of the others is the master system. It might be that depression is a collection of multiple different diseases, and some are caused by one thing and others by another. It might be that looking for a “master system” is silly and that the true mathematical relationship between all of these things is such a chaotic process that all you can say is that they all stumbled together into the wrong attractor point and things deteriorated from there.~ Scott Alexander from, http://slatestarcodex.com/2015/01/05/chronic-psychitis/
This is one of those stories where science has been carefully teasing something apart for many years, only to find out, in the end, that they had it all wrong along the way.
Clarity: SCIENCE FOR THE WIN.
But — via my confirmation bias — this jumps out as another place where being “certain” about things turns out to be — wait, no — I’m not certain. Dammit. Oh well, it’s just turtles all the way down.