When I returned to graduate school for the third time around, this time in systems engineering, I had in mind integrating my long‑standing projects investigating the dynamics of information, inquiry, learning, and reasoning, viewing each as a process whose trajectory evolves over time through the medium which gives it concrete embodiment, namely, a triadic sign relation.

Up until that time I don’t believe I’d ever given much thought to sign relations that had anything smaller than infinite domains of objects, signs, and interpretant signs.  Countably infinite domains are what come natural in logic, since that is the norm for the formal languages it uses.  Continuous domains come first to mind when turning to physical systems, despite the fact that systems with a discrete or quantized character often enter the fray.

So it came as a bit of a novelty to me when my advisor, following the motto of engineers the world over to “Keep It Simple, Stupid!” — affectionately known by the acronym KISS — asked me to construct the simplest non‑trivial finite example of a sign relation I could possibly come up with.  The outcome of that exercise I wrote up in the following primer on sign relations.

• Inquiry Driven Systems • Sign Relations : A Primer
• Inquiry Driven Systems • Semiotic Equivalence Relations