Cycles

Fifteen mentions:

Omnipotent, a lonely seer of Time,
Inward, inscrutable, with diamond gaze.
Attracted by the unfathomable regard
The unsolved slow cycles to their fount returned
To rise again from that invisible sea.
     — Book 3 Canto 1

The aeons ever repeat their changeless round,
The cycles all rebuild and ever aspire.
     — Book 3 Canto 4

The wise think with the cycles, they hear the tread
Of far-off things;
     — Book 10 Canto 1

Vain are the cycles of thy brilliant mind.
     — Book 10 Canto 1

These verses can be related to the myth of Prometheus (Also see The Cycles of the Mind).