Persecution and the Art of Writing
The introduction is operating on at least three levels. Strauss is writing about al-Farabi, who is writing about Plato. It is a little challenging to keep track of who is talking about whom.
Philosophers were essentially persecuted in Greece. They were not popular with the people nor with the government. This persecution created a duality in writing, an esoteric and exoteric message, one for the common people, and one for fellow philosophers who know the code. Interestingly, in Judaism, this idea is supported both by philosophers such as the Rambam in his Guide to the Perplexed and the mystical Kabbalists with their ideas of nigleh and nistar. Once again, at another level, it is possible that Strauss' work itself is written at both levels, containing hidden messages to his initiates.
Interestingly enough, the persecution of philosophers had led Plato and his disciples to the belief that it is the philosophers that represent the highest ideal of mankind. This seems to me very similar to the idea of the Jews viewing themselves as God's special people even as they were being degraded and persecuted by the Gentiles.
I hope to finish the Introduction in the next couple days and move on to the actual meat of the book.