Choose an example of emerson's idealism as displayed in his work.

immersion in nature is true happiness
living in nature is a tough choice because it is dangerous
living off the land is not as fulfilling as he would have hoped
nature is not able to repair any human sadness

The best and most correct answer among the choices provided by your question is the first choice "immersion in nature is true happiness"

Emerson is often characterized as an idealist philosopher and indeed used the term himself of his philosophy, explaining it simply as a recognition that plan always precedes action. For Emerson, all things exist in a ceaseless flow of change, and “being” is the subject of constant metamorphosis. 

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