all the members of the preceding stratum, even though the possibility of their meeting did in fact exist.
To clarify what I have just said about the kinds of figures being recorded, let me point out that one could, if one wished, place all the narrators among the Companions in a single stratum. It is, however, equally possible to divide the Companions into more than one stratum on the basis of transmission, for a Companion may report directly from the Prophet—peace and blessings be upon him—or he may transmit from another Companion.
Likewise, when we speak of the senior tābiʿūn (Successors), we might treat them as one stratum; yet, once the scope of the Successors is broadened, scholarly precision requires that they be split into more than one stratum. The senior Successors are those who narrated from the senior Companions, whereas the junior Successors are those who narrated from the junior Companions, for they never met the senior Companions. Moreover, some Successors transmitted only from fellow Successors—a distinction well known to specialists in this noble discipline.
Accordingly, were al-Dhahabī, for example, to compose a work on all the Qur’an reciters rather than on the “senior” reciters alone, he would inevitably have had to increase the number of strata, and so on.
From this it becomes evident that the stratum assigned to any given biographee is determined by the particular book in which he appears. Hence we cannot expect to find a single, uniform distribution of biographees across all of al-Dhahabī’s works that are arranged by strata. We cannot simply say, “So-and-so belongs to such-and-such a stratum according to al-Dhahabī”; rather, we must say, “He belongs to such-and-such a stratum in such-and-such a book.”
If that is so, it follows a fortiori that no unified stratification scheme exists among Muslim authors in general. Thus, for instance, Makḥūl is placed in the third stratum of the people of Syria by Ibn Saʿd (1), in the second stratum by Khalīfa (2), in the fourth stratum by al-Dhahabī in al-Tadhkira (3), and in the fifth stratum by Ibn Ḥajar in