network-single-justification-removal-blocked
IN premise
`remove_justification()` raises `ValueError` when a node has exactly one justification, forcing callers to use `convert_to_premise` or `retract` instead — preventing accidental creation of unjustified non-premise nodes.
Summary
When you try to remove the only justification from a derived node, the system throws an error instead of silently leaving the node in a broken state with no logical support. This forces you to make an explicit choice — either convert it to a premise (a standalone fact) or retract it entirely — so you never end up with a node that claims to be derived but has nothing backing it up.
Details
| Source | entries/2026/05/11/reasons_lib-network.md |