The Talmud relates that when the Maccabees gained the upper hand over the Syrian Greeks they wanted to rededicate the Temple and light the Menorah but the Greeks had defiled all the oil. They searched the Temple and found one small jug of pure oil that had the seal of the High Priest. They lit the Menorah and the oil lasted for eight days.
The Chassidic commentaries tell us that the miracle of the oil was a reflection of the general story of Chanukah. The Greeks were great philosophers and they believed that intellect and rationalization reign supreme. They were bothered that the Jews believed that the most important thing was to follow G-d and his Torah, even when at times the directives of the Torah are not rooted in logic. As many other dictatorships, they began trying to get the Jews to change their ideologies by a combination of brutal force and persecution. Many Jews started to accept Greek philosophy.
This is the meaning of: “The Greeks contaminated all the oil”. In Jewish writings oil is a metaphor for wisdom and when the Jews started to accept the Greek philosophy, they became steeped into it and their minds became incapable of relating to the Jewish mode of thought.
But, then they found a small jug of oil that was pure. The commentaries explain that part of the miracle of Chanukah is that G-d gave the Jewish people a new inspiration and insight of yet a higher pure intellect, where they were able to comprehend that the true illuminated path of living is when it is based on G-‘s will in this Torah.
History has shown us that at times societies whose modes of life were based mainly on philosophy committed great atrocities. In our times, prior to World War II, Germany, was considered the center of the world in regards to philosophy, the arts and sciences, yet they committed one of the greatest atrocities of history.