Today's daf, and what it says

This is the first page of the Talmud, and already in the first line something is odd. It opens with a short mishnah, five lines, that walks into a conversation already under way:

מֵאֵימָתַי קוֹרִין אֶת שְׁמַע בָּעֲרָבִין?

From when do we recite the Shema in the evening? Look at the first word. From when. Not what the Shema is, not whether you must say it. The mishnah assumes you know, and goes straight to the timetable.

And that is what troubles the Gemara. Its first question in the whole Talmud is not about law. It is about context: where is the tanna standing? What is he leaning on, that he can ask "from when" as if the obligation were already agreed? And a second question at once: we say Shema morning and evening, so why open with the night?

One answer settles both. The tanna is standing on a verse, "when you lie down and when you rise", and in the verse lying down comes first. From there he takes the obligation and the order together. The Gemara offers a second route too: creation. "And there was evening and there was morning, one day." A day in the Torah begins at sunset, so whoever describes a day begins at night.

Then an objection, an answer, and the page moves on to the question it will spend the next several pages on: from what hour, exactly, does the evening begin. The first page is not an opening. It is a continuation.