The lines: "So Eden sank to grief, so dawn goes down to day. Nothing gold can stay." are from the poem by Robert Frost, 'Nothing Gold Can Stay.' We can see that this poem combines condensed metaphor and vivid description.

We can also agree that "Nature's first green is gold" because the pale green leaves of early spring are gold like in their light-reflecting tints, as well as in their preciousness and promise. It is the "hardest hue to hold" because its appearance soon changes and its ideal beauty flees the mind. The green-gold leaves darken quickly, a change that symbolizes the brevity of all ideal heights.

As well-known critic William H. Pritchard pointed out, the word "subsides" provides the poem's point of balance. It is a gentle replacement for an expected term of expansion or growth, and suggests a sigh of disappointment as the leaf turns out to be nothing more than a leaf. It is not a flower. Plus, the more immature leaves are replaced by advancing ones. The fall of humanity in Eden came by such a process. Starting from a height, it plunged the race into knowledge of natural decay.

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