Waxing philosophical on New Year's Eve, it really doesn't suit me. And quoting Joyce's great work looks a little pretentious. But it's the circularity of the thing that appeals to me; no beginning, no end.
I think it was brought on by thoughts of mortality (some things must end, or change in substance). Witnessing an approaching year and wondering if I'll see it out. Eheu fugaces! Positioned Janus-headed at the end of one year and the beginning of another (spurious juncture) I join with my peers in expression of pious hopes for better times ahead. Meanwhile all the signs point to worse to come, in a world in which the warmongers and the grand larcenists are in the ascendant.
Old Machiavelli suggested that "... he who would foresee what has to be should reflect on what has been." In other words, more of the same, my dears. I reckon he got it right.