The three universal rules

Every classification in the system obeys three rules. They are concise; the rationale for each follows.

1. Autonomy

Library systems group disciplines under umbrella prefixes (Science/Physics, Art/Painting). TomeTrove drops the umbrella: Physics and Painting stand on their own. This keeps paths short and treats every discipline as a first-class browse target. Science survives only as a catch-all for general-science works that span disciplines.

2. Substantivization

Every noun is singular. "Italian Literature" becomes Literature/Italy — the adjective "Italian" is recast as a sector noun (Italy) at the next level. "Classical Music" becomes Music/Classical. "Cats/Behavior" becomes Cat/Behavior. This rule keeps every level a single, singular noun, which makes the hierarchy regular and translatable: each level is one term, not a phrase.

3. Instrumental disambiguation

A Shakespeare play script has Type Theatre. A critical essay on Shakespeare has Type Essay. Both share the genre Theatre, but the Type separates the work from its study. This avoids duplicating the genre tree into "creative" and "critical" branches.