Dependencies

A dependency states that one unit is an actual conceptual prerequisite for understanding another. Add it when the learner needs that knowledge first, not merely because studying it earlier would be convenient. Learning paths express goals and alternatives; dependencies express required prior knowledge.

The content and graph must agree. A unit may assume everything taught by its dependencies and should explain other knowledge it introduces. If substantial required knowledge is reusable, make it an explicit unit and dependency rather than hiding its teaching inside the dependent unit.

When several branches require the same concept, point them to one shared prerequisite instead of embedding parallel explanations. Keep dependencies minimal but truthful: omit edges made redundant by transitive prerequisites, but never omit a required concept simply to make the graph look smaller.

See Curriculum units for unit boundaries and Writing content for the final learner-content standard.