Reasoning Engine

The reasoning engine takes Spindle Lisp extracted by the Scanner from across the entire vault, merges it into a single theory, and computes conclusions using Defeasible Reasoning. Every conclusion carries full Provenance — you can trace any result back to the exact file and line that contributed to it.

Pipeline

1. Extract — Scanner finds SPL blocks in Markdown fences and .spl files
2. Parse — spindle-parser converts SPL text into rule objects
3. Provenance — source file, line number, and page name are attached to each rule and fact
4. Combine — all rules and facts are merged into a single theory
5. Validate — check for undefined labels, duplicate definitions
6. Reason — spindle-core computes conclusions
7. Annotate — each conclusion is traced back to its proof sources

(given spindle-core-integrated)
(given four-conclusion-types)

Conclusion types

The engine produces four types of conclusion — see Defeasible Reasoning for details:

Feature gate

The reasoning engine is compiled only when --features reason is enabled — see Feature Gates. Without it, zetl reason prints a clear error rather than failing silently.

See also: Reason Commands, Provenance, Spindle Lisp