The analysis of the Amoraim is generally focused on clarifying the positions, words and views of the Tannaim. These debates and exchanges form the "building-blocks" of the gemara; the name for such a passage of gemara is a sugya (סוגיא; plural sugyot). A sugya will typically comprise a detailed proof-based elaboration of the Mishna. Every aspect of the Mishnaic text is treated as a subject of close investigation. This analysis is aimed at an exhaustive understanding of the Mishna's full meaning.
In the Talmud, a sugya is presented as a series of responsive hypotheses and questions - with the Talmudic text as a record of each step in the process of reasoning and derivation. The Gemara thus takes the form of a dialectical exchange. (By contrast, the Mishnah states concluded legal opinions - and often differences in opinion between the Tannaim. There is little dialogue.) The disputants here are termed the makshan (questioner, "one who raises a difficulty") and tartzan (answerer, "one who puts straight").
The gemara records the semantic disagreements between Tannaim and Amoraim. Some of these debates were actually conducted by the Amoraim, though many of them are hypothetically reconstructed by the Talmud's redactors. (Often imputing a view to an earlier authority as to how he may have answered a question: "This is what Rabbi X could have argued...") Rarely are debates formally closed.
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