Zaid b. Aslam: see Muw. i. 20 and Zurqānī, ad loc.; and below, p. 251 f.

Zuhrī: he is the common transmitter of most Medinese traditions directed against the temporary marriage (mut'a): see below, p. 267. See further above, p. 162; below, pp. 186, 199, 222, 246. Zuhrī himself is hardly responsible in the greater part of these cases.

The existence of common transmitters enables us to assign a firm date to many traditions and to the doctrines represented by them. This consideration which takes into account the fictitious character of the higher parts of isnāds, must replace the uncritical acceptance at their face value of isnāds, as far back as the time of the Companions.¹ We must, of course, always reckon with the possibility that the name of a common transmitter was used by other, anonymous persons, so that its occurrence gives only a terminus a quo. This applies particularly to the period of the Successors. We shall discuss the typical case of Nāfi' in the following chapter.

Similar considerations apply to the isnāds of traditions relating to history.²