[kachnuv_ocasek]

> a system cannot be both sound a complete

Huh, what do you mean by this? There are many sound and complete systems – propositional logic, first-order logic, Presburger arithmetic, the list goes on. These are the basic properties you want from a logical or typing system. (Though, of course, you may compromise if you have other priorities.)

[lemonwaterlime]

My take is that the GP was implicitly referring to Gödel’s Incompleteness Theorems with the implication being that a system that reasons completely about all the human topics and itself is not possible. Therefore, you’d need multiple such systems (plural) working in concert.

[eru]

That doesn't make much sense.

If you take multiple systems and make them work in concert, you just get a bigger system.

[Jeff_Brown]

A collection of systems is itself a system. The theorem would not recognize the distinction.

[jijijijij]

I believe, neither the expansion of Gödel's theorems to "everything", non-formalized systems, nor the conclusion of a resolution by harnessing multiple systems in concert, are sound reasoning. I think, it's a fallacious reductionism.

[tossandthrow]

None of these systems are both sound and complete.

first-order logic is sound, but not complete (Ie. I can express a set of strings you can not recognize in first-order logic).

[tossandthrow]

Yep - when you use a multiplum of systems, then some systems can be regarded complete while other systems are sound.

This is in contrast to just one system that attempts to be sound and complete.