- Author
- Ben Overmyer
- Published
- 28 September 2026
- Kind
- Personal blog post, from a working generator
- Original
- benovermyer.com/blog/2026/09/japanese-vs-western-heraldry/
- Subject
- Images made by rules
- Themes
- Rules that generate, How forms evolve
What it is
Ben Overmyer compares Western heraldry and Japanese mon from a programmer's view. The question comes from building generators for Iron Arachne. Heraldry is treated as primarily descriptive, and mon as primarily compositional.
What it says
- Blazon behaves like a constrained language, so a generator can describe first and then render.
- Mon can be generated directly from geometry: duplicate a motif, rotate it, then enclose it.
- Earlier choices should constrain later ones, as the rule of tincture does.
- A grammar covers normal construction, while a corpus records attested exceptions such as Jerusalem's arms.
- A state machine may control generation, while a tree represents the finished design.
- Generators should begin by asking what operations exist, not what objects exist.
What evidence it gives
The evidence is the author's experience with a working generator and the historical examples discussed. A reading list cites standard references. The post reports no tests of the proposed design, which it calls future work.
Interests and limits
Overmyer warns that neat rules can be classifications imposed afterward by people explaining a tradition. The goal is fantasy symbols, not historical accuracy. The descriptive and compositional split is offered as useful rather than absolute.
Connections
These links are this wiki's own reading, not claims the sources make.
- DSLs Enable Reliable Use of LLMs. In heraldry, choosing the field limits what may follow. Joshi's interfaces do the same, allowing no action before a client. Blazon and a small DSL both make wrong output hard to say.
- Agent memory as a file format. Overmyer lets a state machine run generation while a tree holds the design. Paterson keeps memory as data, apart from any pipeline. Both separate what lasts from the process that produced it.
- John Coltrane's Tone Circle. Overmyer asks which rules belonged to a tradition and which came afterward from its explainers. Hollander collects many readings of one Coltrane drawing. The same question applies: which of this geometry was Coltrane's?
- Mathematical Patterns in African American Hairstyles. Overmyer asks which rules a tradition held and which came later from explainers. Gilmer's braiders use tessellations without seeing them as mathematics. So a rule can live in the hands before anyone writes it down.
- The Secret History of Knocking on Wood. Breen weighs a tidy modern origin for knocking on wood against an older, messier one. Overmyer's question applies: which story came from the tradition, and which from its explainers? Gesture, Breen notes, is rarely written down.