It is exceedingly difficult to differentiate on formal or stylistic grounds among the layers of the Mishnah, which is the document of rabbinic Judaism first brought to redaction. The two Talmuds then lay matters out so as to represent themselves as the logical continuity from the Mishnah. They do so by breaking up the Mishnah into minute units and then commenting on those discrete units of thought. Consequently the Mishnah as a document, a document that presents its own world view and its own social system, is not preserved and confronted. Nor do the Talmuds present themselves as successive layers built upon but essentially distinct from the Mishnah. Rather, the Talmuds aim at completely harmonizing their own materials both with the Mishnah and among themselves, despite the self-evidently contradictory character of the materials. Once more, we observe, there are limits to disagreement. The continuing contentiousness of the documents, their preservation of diverse viewpoints on single issues, underline the rigidly protected limits of permissible disagreement. Intense disagreement about trivialities powerfully reinforces basic unities and harmonies. The fact that out there were Jews who decorated synagogues in ways the Talmuds cannot have led us to anticipate is mentioned only in passing, as if it is of no weight or concern. What matters to this literature is not how the Jews lived nor even how they worshiped, but only the discussions of the rabbinical schools and courts. What the documents say is What we are supposed to think, within the range of allowed difference. Consequently the intellectually unitary character of the sources is powerfully reinforced by the total success of the framers and redactors of the sources in securing stylistic unity within documents and, in some measure, even among them.
Jacob Neusner, Rabbinic Literature & The New Testament: What We Cannot Show, We Do Not Know (Valley Forge, PA: Trinity Press, International, 1994), 25-26.