Comments on “Part Two: Taking reasonableness seriously”


outside all systems?

Lawrence D'Anna's picture

meta-rationality is “reflective”—it stands outside all systems

If what you mean by “systems” is something like “formal systems of thought devised by humans”, then I’ve got no objection.

But if you mean “systems” in a much broader sense, then I do object. Meta-rationality doesn’t stand outside the ecosystem. It doesn’t stand outside the central nervous system of the person doing it. Like any human activity, meta-rationality is contained in and constrained by the limits of the systems it is embedded in.

We can use a rationalist system of thought, called “biology” to study the ecosystem. And the formal methodologies used by biologists can be supervised by meta-rational reasonableness. But that is still taking place inside the brain of an animal. That animal needs to eat or it will die. Eventually it will die anyway. These are biological facts. The human is bounded and constrained by the ecosystem.

At the same time the ecosystem is bounded by the products of human thought. If a human gets the idea in his head to build a bunch of nuclear weapons and put them in rockets and gives one man the choice to launch those rockets, then well maybe it has the deterrent effect they were looking for and maybe it wipes out life on earth.

Systems of all kinds have hierarchical relationships with each other. The nest inside each other like Russian dolls. But if you pursue these relationships far enough things often get weird. Peano’s axioms (PA) is a formal system which nests inside Zermelo-Frankel set theory (ZFC). It nests in the sense that statements and objects and proofs inside PA can be translated into their equivalent in ZFC. Anything you can say or prove in PA you can do in ZFC, but not the other way around. But ZFC is also limited. For example Cohen proved ZFC can’t decide the continuum hypothesis. What axioms do you need to prove Cohen’s theorem? All you need is PA. Weird.

Every system exists in a context that bounds and constrains its operation. Often that context is consists of other systems. Other systems that supervise it, or physically contain it, or create the preconditions for its existence. But these hierarchical relationships do not fit together into some great chain of being with an uber-system at the top. Instead, because each of these hierarchical relationships can be of a different character than the others, the systems form an interconnected web.

But even calling it a web exaggerates the unity of the thing. It temps you to say “maybe the uber-system is the network”. That kind of systemization has its place. An operating system is an interconnected web of programs, which are each themselves systems of instructions. An ecosystem is an interconnected web organisms, which are all independent biological systems. Mathematical logic is an interconnected web of formal systems which can embed in, describe and prove theorems about each other.

But as well as systematization-as-network works, it can’t systematize everything. It can’t grow to encompass everything. Reality itself does not seem to be a system. Every system exists in some kind of environment and is limited by that environment. There is no one system to rule them all.

Systems in a formal sense

If what you mean by “systems” is something like “formal systems of thought devised by humans”

Yup, exactly! Elsewhere I defined “system” in the relevant sense:

by “system” I mean, roughly, a set of rules that can be printed in a book weighing less than ten kilograms, and which a person can consciously follow.

When you write:

Reality itself does not seem to be a system. Every system exists in some kind of environment and is limited by that environment. There is no one system to rule them all.

… we are in profound agreement. This is the essence of my critique of rationalism, and the motivation for meta-rationality. That doesn’t attempt to create a meta-system, but rather works with multiple systems as all inherently limited, and as unable even in combination to fully grasp reality, which will always be more complex and nebulous than we can imagine.

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This page introduces a section containing the following:

This page is in the section In the cells of the eggplant,
      which is in ⚒ Fluid understanding: meta-rationality,
      which is in ⚒ Sailing the seas of meaningness,
      which is in Meaningness and Time: past, present, future.

The previous page is Interlude: Ontological remodeling.

This page’s topic is Rationalism.

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