بَيَانُ الْفَصْلِ وَالْوَصْلِ وَمَوَارِدِهِمَا
A treatment of separation, coordination and their appropriate contexts.
First: waṣl joins clauses appropriately; faṣl omits such coordination.
Second: determine whether the first clause holds a syntactic position and whether the next is meant to share it.
Third: with wāw, look for a genuine common relation rather than verbal resemblance alone.
Fourth: separate clauses when coordination would wrongly extend a judgment or misattribute a statement.
The subsequent account of complete connection, complete disjunction and their intermediate forms develops these distinctions into a systematic framework.