For reference:

> https://en.wikipedia.org/wiki/Knowledge   
> https://plato.stanford.edu/entries/knowledge-analysis/  
> https://plato.stanford.edu/entries/knowledge-how/  
> https://plato.stanford.edu/entries/structural-realism/

I came close to abandoning this question for it seemed just another version of: "Do objective facts exist?", "Is there non-empirical knowledge? and so on. But trying to express my meaning of "structure", I realized all examples had one thing in common: the human mind. Then realized that any non-human-mind related (objective?) structures I manage to communicate would actually be subjectively imposed. (So maybe now I _truly_ get what "A-thing-in-itself" is?)

But we're talking about structure, not things. And immediately I hear "Structures can be described and studied, hence they are knowledge also." However I submit that this is like English being its own meta-language, and that these are human-mind constructions. Mostly, we cannot assume there is similar relations between objective knowledge and structure as there is between our own constructs.

**Question: Are there any philosophers who have studied the (possible) metaphysical difference between knowledge objects and objective structures?**