In the introductory portion of Emerson's Nature, what does he mean by "Our age is retrospective. It builds the sepulchres of the fathers."? If possible can an analysis of the introductory portion be given to have a better understanding of his intentions to readers?
History teachers would not like this quote from Emerson. What he is saying is that the people (of Emerson's time) too often look back to history to learn more about their present situations. That's what retrospective means. Looking back. The sepulchre portion is Emerson saying that we build vast tombs and monuments to remember and glorify people from the past. Emerson thinks that both of those things are stupid.
Emerson is a transcendentalist, which is a sort of an off shoot of romanticism. A few key features of that time period are the importance of nature and carpe diem. Emerson and Thoreau both thought that transcendent knowledge and wisdom could be attained through a "oneness" with nature. In order to do that, a person had to go out and experience nature and commune with it, instead of sitting back and reading history textbooks.
A few sentences in Emerson lament the fact that the forefathers got to build their ideas through their own experiences and now people only want to learn from them instead of forming their own ideas. "Why should not we also enjoy original relation to the universe . . . why should we grope among the dry bones of the past . . .?" Emerson wants himself and people to think for themselves. Invent for themselves. Experience for themselves. "Let us demand our own works and laws and worship."
The following paragraph tells the reader than Emerson believes all of those answers can be found in the perfection that is nature.
Interestingly, Emerson wrote this down . . . for people to read and learn from. Why? He's telling people not learn from those that came before, so how would Emerson feel about people today reading his stuff?