The tale of the King of Birds, incidentally, refers originally to the Mantíq al-taír, or Conference of the Birds, written by the Persian mystic poet Faríd al-dín Abí Mâmid Muhammad ben Ibrâhím1 (also known as Attâr the Perfumer), the tale of which runs thus :

One of the splendid feathers of the distant King of Birds, the Símurg, one day falls into the center of China; and the slight earthly birds, weary with the present state of anarchy among the animals and the constant fighting for survival resolve to find their king.

They know that the name of their king means '30 birds' and they have heard that his palace is in the Mountains of Kaf, the vast range which encircle the edges of the world.

Regardless of danger, the birds undertake the almost infinite flight.

They cross the seven wadis (seas), the penultimate of these being the Sea of Vertigo, the last being the Sea of Annihilation. Hundreds of the pilgrim flock abandon the search, and just as many tire and die along the way.

At the end, the thirty birds remaining, purified by their travels manage to reach the mountain on which the Símurg lives and they look upon their King at last.

They see that they are the Símurg, and that the Símurg is each, and all, of them.2


Notes:
1 Murdered by Mongol reavers under the command of Tolui, heir of Genghis Khan, during the sacking of Nishapur in 1221. It seems that the city fathers had indelicately refused to pay a tax demanded by the Great Khan in 1218 and had added indecency to indelicacy by executing the tax collectors. This was doubtlessly expressive but definitely not wise. Tolui negotiated a surrender with the understanding that lives would be spared. He lied. Once in control of the city he ordered each of his soldiers to murder 300 to 400 residents. They did this with the sword and added the torch to complete the work. Some believe that over one million people died. The Mongol army left only to return one week later to kill all those who had somehow managed to escape execution in the first round. After that second binge of destruction, the Mongol army assembled and Tolui asked the crowd if any man there had regrets. A single teenaged spearman stepped forward, vowing eternal loyalty and undying love for his general - but he had, before sending his spear through the mouth of an infant left motherless, felt a pang of guilt. "Young warrior, you are honest, true and brave!", was the commander's reply, "You shall stand a testament to the worth and wiles of our might!" So the boy soldier was strung up by a tree branch overlooking the dead city before the horde rode away.
2 Plotinus, who was intrigued by the philosophies of Persia, seems to perhaps have heard this same tale (so intrigued by the East was he, he joined the campaign of emperor Marcus Antonius Gordianus (a/k/a Gordian) against the Parthians, in 243 AD, which ended with that emperor's termination in Mesopotamia3); Plotinus, in his reflections, wrote in his Enneads (V, 8, iv) a passage much like the tale's last line: "Everything in the intelligible heavens is everywhere. Any thing is all things. The sun is all stars, and each star is all stars and the sun."
3 Previously, either by misreading Borges, Sir Richard's text or conflating the two with the preface to Fitzgerald's translation, this assassination was ascribed to the silent Hashsa'im. Mercifully, 23 years later, vongrim spotted that millennial anachronism, and, after double-checking both Ficciones and Burton's 12 volumes, it is confirmed there is only a passing reference to hashish, and none whatsoever to Gordian who, for the record, "seems" to have been slain by his own troops.4 Rendering this whole retelling (and referencing) pretty Borges in its own right.
4 I guess the jury's still out; see David MacDonald's essay, “The Death of Gordian III: Another Tradition.” Historia: Zeitschrift Für Alte Geschichte 30, no. 4 (1981): 502–8. http://www.jstor.org/stable/4435781.


Sources:
  1. Omar Khayyam. The Sufistic quatrains of Omar Khayyam. In definite form incl. translations of Edward Fitzgerald and a general introduction dealing with Omar's place in Sufism, by Robert Arnot. (London : L.B. Tetens, 19??)
  2. The book of the thousand nights and a night : being a plain and literal translation of the Arabian nights entertainments / Sir Richard Burton King’s College, Oxford, 1885 - 88
  3. "The Approach to Al-Mu'tasim", from Ficciones / Jorge Luis Borges. (Madrid : Alianza, 1997)