Authoring Rules

These rules emerged while building the knowledge tree and govern how every node is authored. They keep the graph consistent and the emergent history believable.

Concept vs. Category

Test: Can you point to the moment someone discovers it, and does discovering it unlock something?

• Yes → concept (a genuine, unlockable idea; a graph node).
• Just a label for “the group of praxes about X” → category (a display label, not a node, excluded from discovery logic).

Skill-accumulation things (e.g. “seamanship”) aren’t memes at all — they live on the skill axis.

Prerequisite vs. Size vs. Affinity

Three distinct mechanisms, never conflated:

• Prerequisite = “impossible without” — genuine logical/material necessity, a hard boolean gate. Not for historical sequence.
• Affinity = “easier with” — eases discovery, but a genius could leap past it.
• Size = “how advanced / rare” — an integer the discovery logic divides by; a bigger meme needs a larger or better-conditioned society to arise independently.

Worked example: clear glass doesn’t require glass-blowing (both build on glass founding), so it’s parented on founding, given a large size, and an affinity to blowing — the usual history emerges as probable while divergent history stays possible.

Material, tool & context requirements

These are not a separate mechanism — they are typed prerequisite leaves (material:, construction:, faction:, event:) in the same boolean expression as meme prerequisites. Two authoring rules govern them:

• Materials gate (a) ex-nihilo discovery and (b) execution — never the knowledge of a material (a lore meme) or the transmission of a praxis. The gate-channel is keyed off the leaf kind automatically. A material must be in reach (extracted, grown, or imported); this produces economic geography: a smith’s tin-using praxis puts tin in his store’s consumption profile → below-min → demand → a tin trade route appears.
• Tools (a construction: leaf) must be available (owned/borrowed/bought) but need not be known how to make, and are not consumed. Tools gate the activity, not the knowing.

When a material or crop earns its own praxis

Only when winning it requires a genuinely novel method. Salt did (evaporation, rock-salt mining); sulphur and most minerals did not (general digging/roasting). Likewise a crop earns a dedicated praxis only when its method differs (paddy rice, viticulture) — otherwise it’s general cultivation + a crop material.

Demand precedes intensification

An intensifying praxis (breeding, cultivation, extraction) becomes a discovery candidate only once a society holds a meme that creates demand for the material. You don’t breed for wool before you weave, or farm woad before you dye.

This is a runtime gate, not an authoring exclusion

The meme always exists in the tree (the tree is the full space of what can be known); demand only gates its discoverability at runtime. Flagged for reframing in Design Status.

Granularity & scope

• Coarse-to-medium granularity. One praxis per distinct capability; it earns its place only if it enables a new process or embodies a real historical breakthrough.
• Scope: up to the Renaissance. No firearms (deliberately absent). Gunpowder exists as knowledge but flowers into mining-blasting, demolition, signalling, and fireworks.

Fields of knowledge (15)

Each field is an organising tag and an affinity generator (same-field memes mutually reinforce).

Built (12): Metallurgy · Extraction · Agriculture · Construction · Textiles · Scholarship · Ceramics & Glass · Maritime · Chemistry · Food & Drink · Commerce · Art. Remaining (3): Military · Governance · Medicine.

Art is special: beyond its standalone outputs, its praxes act as a combinatorial layer — paired with a base craft in a recipe they open that craft’s decorative/refined tier (relief carving

• masonry = a carved capital).