I wonder about the coherence of saying that everything is relational, with no non-relational relata. You say systems relate to each other, but if the systems are made of more relations between relations, with no intrinsic properties or nonrelational things or substances anywhere to be found, “relation” might lose its meaning.

Buddhists say everything arises dependently on something else, so there’s no sense in taking our simplistic models so seriously. Specifically, those models ignore many causal relations, presenting us with a perceptual field of "things" that we mistake for being permanent, so that we crave their substantiality or their insusceptibility to change, and suffer when relations catch up to them and these things that correspond to our simplistic models change and vanish after all.

But does it make sense to say there could be relations between nothing, or relations without any things that are related? Isn’t this like saying it’s “turtles” all the way down? I suspect that “relation” must be used as a euphemism or a placeholder in this case. The relationist is grasping for a concept of pure structure with no substantiality. Of course, our brains likely evolved to impose these categories onto experience. There may even be masculine and feminine cultural biases at work in this clash between “hard”/substantial and “soft”/relational ontologies.

Your point about indexicality is intriguing.