One view permits describing a suitably corroborated ahad report as yielding inferential knowledge. Another reserves the unqualified word knowledge for the certainty associated with tawatur and calls what lies outside that category probable.
«وَالْخِلَافُ فِي التَّحْقِيقِ لَفْظِيٌّ»
Upon examination, much of the disagreement is terminological.
A scholar reluctant to use the word “knowledge” need not deny that a report supported by sound indicators is stronger than an otherwise comparable report lacking them. The dispute concerns the label attached to this enhanced evidential strength. In each case the claimed indicators still have to be established.