This is not like the Sokal hoax at all. Sure the writer has a few English departmentish affectations, but the article is basically just explaining Peirce's logic. And Peirce is one of roughly two people in history to figure out quantification.

Peirce's diagramatic logic is the forerunner to Sowa's conceptual graphs [0]. Worth a look.

[0] https://en.m.wikipedia.org/wiki/Conceptual_graph

Not sure either. Semiotics is a philosophical branch of linguistics.

De Saussure and Peirce I put conceptually in the same tradition of Cyc and other symbolic/ontological/semantic efforts in knowledge engineering.

That being said, symbol grounding does not get enough attention in current connectionist systems. How to properly present grammar, time, pointers, signs?