Background and common-link theory Common-link theory is an approach in hadith studies which seeks to identify the origins or earlier versions of hadith by comparing reports that have the same content (matn) but have different chains of transmission (isnads). If the chains of transmission converge on a single figure, then that figure may be taken as the original collector of fabricator of the tradition, depending on one's approach or conclusion. Common-link theory originated in the works of
Joseph Schacht and
G.H.A. Juynboll. In his 1950 book
The Origins of Muhammadan Jurisprudence, Schact introduced the concept of the "Common Link" (CL) to refer to the earliest point at which multiple chains of transmission (isnads) intersect. For Schact, the CL was equivalent to the point of origins of the tradition. Later,
G.H.A. Juynboll would systematize earlier applications of common-link theory by elaborating a more consistent set of criteria and terminology. Importantly, he introduced the notion of a Partial Common Link (PCL), which represents points of convergence of multiple isnads taking place among transmitters located after the common link themselves. In other words, a group of traditions may converge at one transmitter, and that transmitters version of a tradition may converge among yet other versions at what is ultimately the common link. While Schact believed that the common link was a legitimate purveyor of the tradition in question, Juynboll introduced the terminology of a "seeming" CL (or PCL) for a concept that Schacht had established, referring to the idea that while several isnads may converge at a particular common link, the common link themselves may be artificial. In reality, several isnads may have been fabricated and, in this case, a particular transmitter only turns up as a common link because several later figures falsely attributed the same tradition back to them. It is up to the investigator to determine if a CL or PCL is authentic, and Juynboll argued that the historical plausibility of a common-link is raised the more PCLs converge on it. Another term Juynboll introduced into common-link theory was a "spider"; this refers to single strands of transmission that completely bypass the CL of many other versions of a report in finding their way to the original figure believed to have conveyed the tradition. Juynboll sees such "spiders" as fabricated isnads. Juynboll referred to attempts to create isnads bypassing the CL or PCL as "dives". Direct forerunners to the ICMA approach, involving the combined study of the isnad and matn, included Jan Kramers' 1953 article "Une tradition à tendance manichéenne" and Josef van Ess in his 1975 volume
Zwischen Ḥadīṯ und Theologie. The formal development of ICMA would only come with the work of
Harald Motzki,
Gregor Schoeler, and
Andreas Görke in the 1990s.
Invention ICMA was invented twice independently in two publications that came out in 1996, one by Harald Motzki (in an article where the name of the method was given) and the other by Schoeler. The primary advocate of ICMA in the initial stages of the development and application of the method was Motkzi; Motzki believed that the oral transmission of hadith would result in a progressive divergence of multiple versions of the same original report along different lines of transmitters. By comparing them to pinpoint shared wording, motifs and plots, the original version of a hadith that existed prior to the accrual of variants among different transmitters may be reconstructed. In addition, Motzki believed that a comparative study of the differences between reports could enable the identification of particular manipulations and other alterations. == Terminology ==