Early this morning, I attended a talmud class in which the 39 classes of m'lacha were being discussed. The focus of the discussion was the Mishna (Shabbat 72a) that lists the general classes. And the magid shi'ur (lecturer) cited a comment by a R. Mordechai Benat in "Magen Avot." I found the comment esthetically pleasing, and am passing it on to those of you who might enjoy it:
The mishna lists the activities beginning with "ha'zorea" (one who sows [seeds]). But the Rambam's list is of the form "z'ri'ah" (sowing).
The difference in literary style is significant. There is a running dispute throughout the tractate of Shabbat about whether a m'lacha sh'eino tz'richa l'gufa (MSTL, an act not done for its own sake, e.g., cutting branches not for the wood or for pruning, but for exercise) is forbidden. Rav Shimon says MSTL is not forbidden; Rav Yehuda says that it is.
The mishna apparently agrees with Rav Shimon; whether an act is forbidden depends on the intent of the individual, so the individual must be sowing, or reaping, etc.
The Rambam, however, rules according to Rav Yehuda: MSTL is forbidden. It is the _act_ that counts, not the intent. Thus, the Rambam forbids _sowing_ (not _one who sows_).
Lovely, IMHO. Just lovely.