> Any self-consistent body of knowledge can be reduced to a number of clear elementary postulates from which everything else logically follows.

I'm not sure why the author thinks this would be true.

Or why by implication the inverse is false.

It appears to be the case. The world is a very complex place, but fundamentally every detail of it is emergent from a small body of rules and mechanisms, which we call quantum mechanics. The love you feel derives from that ultimately.

It is fractal in nature. So it would follow that any correct set of ideas derive from some principles, and if the principles have a lot of corner cases that require caveats then you're missing something and you don't have the principles hammered down after all.

I look around using a torch and everything I look at, everything I can see, is lit.

So the natural and correct conclusion is that all objects are lit, right?

That's a bad analogy. You don't have to act on the world viewing it through a paradigm.

We KNOW that quantum mechanics is incomplete. Everything is definitely not described by quantum mechanics.

Not by the current standard model, no, but there is a fundamental model, that we know a thing or two about at least, that describes the complexity we see happening around us.