Answer:
Ebbs and flows in this context mean that human misery comes and goes.
Explanation:
The poem, Dover Beach, written by Matthew Arnold, uses the term 'ebbs and flows' to describe how human misery comes and goes. Ebbs and flows, in the context of sea movement, refers to the coming (flows) and going (ebbs) of the sea tides.
We can say that though hardships and miseries are experienced by all humans, eventually, it would all go away, drifting into the sea as we continue to live on and experience more happiness and betterment flowing in.
The stanza referred is this excerpt:
Sophocles long ago
Heard it on the Ægean, and it brought
Into his mind the turbid ebb and flow
Of human misery; we
Find also in the sound a thought,
Hearing it by this distant northern sea.
