Rav Shimshon Pinkus made an interesting note. On the holidays, we say the bracha, "Who sanctifies Yisroel and the times…" Regarding Shabbos, we make a bracha "Who sanctifies the Shabbos," but we make no mention of the Jewish nation. He explains that this is because Shabbos is for the whole world. There is a special light of holiness that comes into the world on Shabbos. While it is true that Shabbos is a special time for the Jewish people as a whole, its holiness fills the world. The holidays are different. There is a special holiness to them as well, but they are specifically set for the Jewish people and do not affect the entire world.
Chanukkah is different than the previous two. Like them, we light candles. However, nowhere do we make a bracha on the holiness of the day.
On Shabbos and Yom Tov, there is a special holiness, and for each of those days, we have special "spiritual tools" at our disposal that we normally do not have. If we use those tools properly on those specific days, we can harvest enough of that holiness for the rest of the week/year.
Chanukkah on the other hand lacks this holiness. In fact, we have a special halacha that the Menorah should be within 10 tefachim (handbreadths) from the ground. The days of Chanukkah themselves do not create these special tools. On Shabbos and Yom Tov, when we eat a meal, it automatically becomes a mitzvah. On Chanukkah, if the meal lacks dvrei Torah, it lacks any mitzvah.
Greek culture, as we know, focused solely on the physical world. There was no spirituality. Everything was based on physical and intellectual beauty. Chanukkah comes and destroys that notion. On one hand, we do not subscribe to the idea that the physical world is just an agent of Satan. On the other hand, we do not subscribe to the idea that there is no spiritual world. We believe that Hashem gave us a physical world to use as a tool to increase our spirituality. That means, taking the physical, however mundane, and making it spiritual.
When a person goes to his nine-to-five job, for example, and conducts his business according to the Torah, and does so in order to support his family and others, he is taking something mundane and making it holy. Another person, who does so for the sake of acquiring money and power with little or no regard to Jewish law, is taking that mundane and using it for the opposite.
The world, in general, does not believe or does not…invest, in the spirituality of man. They focus on what they see and how to use it for their own personal, physical, purposes. Some use it for good, some use it for bad. But we? We don't use it for physical. We use it as a tool for spiritual growth, and this is one of the many main lessons of Chanukkah. Hashem does not create the holiness of these days, we do.