(Vilification of Hellenism. From the mudswamps of Hella link):
https://www.chabad.org/holidays/chanuka ... Battle.htm
... More subtle are the ideological challenges: doctrines and philosophies that lay claim to virtue and truth, and might even espouse altruistic behavior and transcendent aims, but are utterly alien to the Jewish soul. A Jew disconnected from his roots and ignorant or unappreciative of his heritage is ready prey for the foreign waters that offer to quench his spiritual thirst.
But infinitely more noxious is a third category: doctrines that blend the soil of materialism and the fountains of reason into a lethal muck.
A person buried in corporeality can claw and dig his way out to sunlight. A person sinking in a sea of spurious reason can struggle to the surface and swim to shore. But he who adds water to his soil—who saturates his materialism with intellectual fluid—creates a morass from which it is infinitely more difficult to extricate himself. When his soul is moved to reach beyond the mundanity of the material, a host of rationalizations rise to still its yen; and when his mind begins to wake to the fallacy of the alien creed, the grasp of earth pulls him down. The person is thus steadily sucked down, as his efforts of mind and will to rise above his mired state are counteracted by the bog of idealized hedonism.
Such was the challenge that faced our forefathers during the Greek domination of the Holy Land. Yavan, the Hebrew word for the Hellenic culture, means mud [?!] (as in Psalms 40:3—see Rashi and Metzudat Zion commentaries on verse). The Hellenic reformers did more than entice and coerce the people of Israel to embrace the body-worship of Greece—they also sought to indoctrinate them with a philosophy that exalted the physical and made its worship a virtue and an ideal. The Greek was not merely pagan; his was a paganism aestheticized by art, glorified by poetry and hallowed by reason. The Greek was no mere materialist, but one who kneaded his earthiest wants with the subliminal waters of his intellect to form a mucilage that fastened on the soul and drew it, inch by inch and limb by limb, into the quagmire of Yavan.
The deadliness of the mudswamp is further illustrated by the very form of the Hebrew word Yavan, ( יון ) whose three letters are three lines, each descending an increment lower than its predecessor. Unlike water, in which one might sink swiftly to the bottom but can also, equally swiftly, pull himself out, the mud of Yavan works slowly, drawing the person down bit by bit, step by step. At first, it only demands a slight, barely discernible departure from ones convictions and morals. But its downward pull is steady and all but irreversible—indeed, all efforts to extract oneself by the means of ones conventional faculties are doomed to failure—except by the extremely potent power of faith, as explained in the text. ...
This is the eternal lesson of Chanukah: intellect might be mans highest faculty, but it can also be the instrument of his degradation to the lowest depths.
Chanukah celebrates the cleansing of the Holy Temple from Hellenic corruption, the triumph of the pristine essence of the Jewish soul—represented by the small, pure cruse of oil that burned in the menorah for eight days—over the mud of Greece. ...
In broader terms, it seems to celebrate a victory of superstition (irrationality) and faith over reason.