Decades

There Will Be Time, II, III.

Appropriately in a novel about time travel, Poul Anderson contrasts the 1950s with the 1960s but from an oblique angle:

in 1951, Robert Anderson reads the time-traveling Jack Havig's mimeographed parody of 1960s youth rebellion;

in the 1960s, Robert Anderson experiences that decade for himself like everyone else;

in the early 1970s, Robert Anderson reminisces, then dies, having bequeathed material for a novel to Poul Anderson.

I may add that I am blogging about the novel in 2020 but not in the same timeline as Jack Havig. Our War of Judgment is still ahead.