Why were books of philosophy available in the orchestra in Platos time?

Question

This isn't a philosophical question per se; but asking for some clarifying background information on a classic book of philosophy.

In Platos dialogue Apologia Socrates mentions that Anaxagoras books are available to purchase for a drachma in the Orchestra:

Socr. O wonderful Melitus, how come you to say this? Do I not, then, like the rest of mankind, believe that the sun and moon are gods?

Mel. No, by Jupiter, O judges! for he says that the sun is a stone, and the moon an earth.

Socr. You fancy that you are accusing Anaxagoras, my dear Melitus, and thus you put a slight on these men, and suppose them to be so illiterate as not to know that the books of Anaxagoras of Clazomene are full of such assertions. And the young, moreover, learn these things from me, which they might purchase for a drachma, at most, in the orchestra, and so ridicule Socrates, if he pretended they were his own, especially since they are so absurd? I ask then, by Jupiter, do I appear to you to believe that there is no god?

This, at least to modern sensibilities seems strange. Is this because in Platos time the muses were associated to the music & poetry and thus by extension to astronomy and the sciences? What actually is an orchestra in Platos time? It surely cannot be a group of musicians - perhaps where they 'hang out'? (It may of course be that this isn't the most appropriate translation of the word).

Answer 1

Orchestra in ancient Greece wasn't only the place of the theater between the stage and the viewers where the chorus was standing but also an open place near the market where books and other items were sold.

I translate the paragraph "Geometric - Archaic period 1100 - 480 BC" from the article "Αρχαία Αγορά της Αθήνας" (ancient market of Athens) from Greek Wikipedia.

"During the Geometric period no special activity is observed and the Market area is called Kerameikos. Around 600 BC Solon transfer the administrative center of the old market (the so-called "Agora of Theseus" that was west of the Acropolis) in the area of ​​Kerameikos. A little later, Peisistratos fortified town and Agora is divided into outer and inner Kerameikos. The Inner Kerameikos became the political center of the city while the Kerameikos Outside was outside the city walls and was the burial of the dead. The name of the Agora and the region as Kerameikos remained until the Roman times.

Major changes were made in the field with the reforms of Cleisthenes that led to the Republic. The new regime require new public character buildings for different functions. The buildings are constructed in the space bounded on the south by the Supreme Court, to the west by Agoraios Colonus and the north by the river Eridanus. The space created between the buildings, is shaped so that it can accept the concentration of civilians and called orchestra."

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