Invent your own symbolic system

Designing a deck, an oracle, or a fictional divination system that has to hold together.

Help me design an original symbolic system, the way tarot or the zodiac is a system rather than a list.

Work through:
1. **The organising principle.** What the structure is built on: a cycle, an opposition, a journey, a hierarchy, a set of elements. Propose three options for my material and recommend one.
2. **The skeleton.** How many symbols, grouped how, and what the groups mean in relation to each other.
3. **The vocabulary.** Where the imagery is drawn from, so the symbols feel like they come from one world.
4. **The grammar.** How two symbols combine, and what happens when they contradict. A system with no rules for combination is just a list.
5. **The gaps.** Which human experiences this structure handles badly, because every system leaves things out and the omissions give it character.

Then draft five symbols in full as a sample, and name the weakest part of the design.

What the system is for:
World or material it comes from:

Writing and craft. Horoscope voice, ritual text, card descriptions, and fiction built from the archetypes.