Recognize it—unless it becomes clear that the narrator was mistaken or confused about a point; once that is evident, it is duly noted. First examine the senior and junior Companions of the Messenger of Allah: every one of them narrated a sunna that was unique to him, and people would still say to him, “No one else reports this hadith!” The same is true of the Followers (tabi'un); each possessed knowledge the others did not. This, however, is not our main concern, for these matters are already settled in the science of hadith. When a reliable narrator (thiqah) is the sole transmitter of a wording, the report is classified as sahih gharib (sound yet singular). If a merely truthful narrator (saduq) or anyone of lower rank is alone in narrating, the report is judged munkar (denounced). A narrator who produces many reports that lack corroboration—whether in wording or chain—comes to be regarded as matruk al-hadith (abandoned). Not everyone who holds a bid'a (heterodox view), makes a slip, or commits sins is automatically discredited in a way that weakens his hadith, nor is it a condition of reliability that a person be infallible. The point of listing many trustworthy narrators who had minor innovations or small errors despite their vast learning is to show that, when others oppose or contradict them, those others may outweigh them in strength and reliability. Therefore, weigh matters with justice and piety. (*) Khalifa, Tabaqat, p. 215; al-Bukhari, al-Tarikh al-kabir 5:410; al-Bukhari, al-Tarikh al-saghir 1:318; Ibn Abi Hatim, al-Jarh wa-l-ta'dil 5:346; Abu Nu'aym, Hilyat al-awliya' 2:309, 318; al-Mizzi, Tahdhib al-kamal, no. 853; al-Dhahabi, Tadhhib al-tahdhib 2/248/2; al-Dhahabi, Tarikh al-Islam 5:104; Ibn Hajar, Tahdhib al-tahdhib 6:389; Ibn Abd al-Baqi, Khulasat tadhhib al-kamal, p. 243; Ibn al-Imad, Shadharat al-dhahab 1:175.