# Tenet

> Stored rules and learned facts in a Mind's Soul — invariants and priors.

A Tenet is a stored rule, belief, or learned fact in a Mind's [Soul](/docs/concepts/soul). Tenets come in two types:

- **Invariants** — [Guardrails](/docs/concepts/guardrail) the Mind will never break, no matter what
- **Priors** — flexible preferences the Mind has learned from use (for example, "this user prefers bullet points")

As the [Steward](/docs/concepts/steward), you can read, edit, or add Tenets at any time. The Mind can also update its own Tenets based on real interactions. Tenets persist across [Brain](/docs/concepts/brain) swaps and shape every future session.