حُسْنُ الْابْتِدَاءِ — بَرَاعَةُ الِاسْتِهْلَالِ
A fitting opening and a hint of the intended theme.
An elegant opening is not necessarily barāʿat al-istihlāl. For that, the opening must anticipate or suitably suggest the main subject. A pleasant but unrelated introduction may still be attractive without offering thematic foreshadowing.
In revising a lecture opening, a well-chosen subject-linked image or term can create this anticipation. Forcing a technical expression into an otherwise natural opening, however, can damage fluency and appropriateness.