Although The Egyptian Tale looks like a retelling of a part of the myth of Isis and Osiris, it is obvious that the two brothers Osiris and Typho represent good and bad government. The story, however, is not just a myth, because the man called Osiris can be identified as Aurelian, praetorian prefect of the Eastern Empire during the reign of Arcadius, and one of Synesius' benefactors. The other people in this ancient roman à clef, however, are less easy to identify, but an attempt is made here.
Synesius, On Providence 1.12
[1.12.1]  When he had finished speaking, he departed, following the same road as the gods, but Osirisnote remained, a marvel ill-suited to this earth, one who at once began striving to banish the forces hostile to the earth, without employing any violence at all. He actually sacrificed to Persiasion, to the Muses, and to the Graces, and made all willingly fall in with the law. The gods gave in abundance - out of respect for the king - all things, as many as the air bears, and as many as are the gifts of river and land, and all these pleasures he gave up to his people for their joy. He himself left all ease behind him, and preferred to undertake every toil, taking small part in sleep but the greatest in cares; in a word, he took no leisure that all might have leisure.
[1.12.2] These acts of his accordingly filled all men, whether individuals, households, relations, cities, or entire districts, with benefits, spiritual and material. For he cultivated amongst them a zeal for virtue, making all knowledge and every institution to be so cultivated for this one end, and he offered rewards to those who were best able to govern men, and to make the governed like themselves. It needs must be that what is honored should increase, that what is neglected should come to nought. A love for all education grew up with him, the part which partakes of reflection as much as that which partakes of eloquence, and the result of this was that men who excelled in knowledge of this sort could no longer be seen mingled in the common herd, but were shining with honors from their sovereign, for they brought with them skill as the handmaiden of wisdom, inasmuch as intellect progresses once it is arrayed in letters.
[1.12.3] And the better or the worse clothing of the same intellect makes it appear, as in a man’s dress, seemly or unseemly. Early education Osiris thought worthy of honor, for he regarded all education as a fountain-head of virtue, and indeed at this period of all others piety was in fashion among the Egyptians. Such are the good things of the soul, and the Egyptians under the reign of Osiris abounded in them, so that the country resembled a training school for virtue,  a country in the which youth looked to one leader, doing the one thing which they saw, and saying the one thing that they heard.
[1.12.4] He himself was indifferent to wealth, but took every care that there should be enough for all, receiving no gifts himself, but delighting in bestowing them. He furthermore remitted taxes to cities, he gave to those who were in distress; he raised the fallen, and healed that which was likely to fall; one city he enlarged, another he trained to be beautiful; where another was lacking, he added it, another that had been abandoned, he helped to people. Of necessity must each man individually profit by benefits which are common to all, but it was no labor for him to condescend even to anxiety for some one individual, and so it came about that no man was seen to weep under his reign; nor was Osiris ignorant of what each man wanted, and what obstacle there was to the happiness of such and such person. One coveted merited honor, and he gave it to him, and when another, through persistence in the study of books, had no time to gain his livelihood, he accorded to him his meals at the town hall. Another was indifferent to honor from men, and although his possessions gave him quite enough to live on, he was perhaps too shy to take up public function. Osiris was not unaware of this, but exempted him from public functions, not annoyed by him, but rather causing him annoyance by offering something he had been asked, and he demanded out of respect for wisdom that such a man be independent and freed from worldly business, as a sacred animal dedicated to God.
[1.12.5] In a word, no one failed of his deserts except such an one as merited misfortune, and to that man he gave not his expected reward. For he made it a point of honor to conquer the most shameless man by the gentleness of his mind and by kindly deeds. In this way, he thought to overcome his brother and his band of conspirators, changing their nature by the abundance of his virtue. But in this one thing he was wanting in judgment, for malignity not assuaged by virtue is rather inflamed by it.  If to cling to the good is natural, to the extent that good increases, the grief occasioned by it increases also, and this is precisely what the deeply groaning brother suffered over the reign of Osiris.