Alexander's teacher Aristotle of Stagira wrote a short treatise On the cosmos, to Alexander. It was a brief treatise on several sciences, such as physics, meteorology, geography, theology. For more than a century, scholars have considered On the cosmos as inauthentic and probably dating from the second century BCE.
In the 1990s, however, it has been shown that the language of this treatise does not exclude a publication in the fourth century. At the same time, Aristotle's philosophy has been scrutinized and a new and completely different view on his ideas has been developed. According to some scholars, On the Cosmos, to Alexander is probably the best introduction to Aristotle's teachings. It may have been written to introduce Alexander to philosophy; if so, the following words must have fired the young man's imagination.
The translation of On the Cosmos 398a11-398b1 was made by D.J. Furley.
Giovanni Reale and Abraham P. Bos, Il trattato "Sul cosmo per Alessandro" attribuito ad Aristotele. Monografia introduttiva, testo greco con traduzione a fronte, commentario, bibliografia ragionata e indici, 1995 Milan
Persian court life
[398a] The pomp of Cambyses and Xerxes and Darius wasnote[The past tense is used because the author is looking back to the golden age of Persia and is not describing the realities of the fourth century. The Athenian author Xenophon (c.430-c.355) also writes about Persia as if its glory days are gone (Education of Cyrus 8.8).] ordered on a grand scale and touched the heights of majesty and magnificence. The King himself, they say, lived in Susa or Ecbatana,note[An indication that On the cosmos, to Alexander was written before 330: after that year, no author would have ignored Persepolis as capital of the Achaemenid empire.] invisible to all, in a marvelous palace with a surrounding wall flashing with gold, electrum and ivory; it had a succession of many gate towers, and the gateways, separated by many stades from one another, were fortified with brazen doors and high walls.
Outside these the leaders and most eminent men were drawn up in order, some as personal bodyguards and attendants to the King himself, some as guardians of each outer wall, called Guards and the Listening-Watch, so that the King himself, who had the name of Master and God, might see everything and hear everything. Apart from these there were others appointed as revenue officials, leaders in war and in the hunt, receivers of gifts to the King, and others, each responsible for administering a particular task, as they were necessary.
The whole empire of Asia, bounded by the Hellespont in the West and the Indus in the East, was divided into nations under generals and satraps and kings, slaves of the Great King, with couriers and scouts and messengers and signal-officers.
[398b] And such was the orderly arrangement of this, and particularly of the system of signal-beacons which were ready to burn in succession from the uttermost limits of the Empire to Susa and Ecbatana, that the King knew the same day all that was news in Asia.