The speaker implores his friend—in fact, the reader may be the friend he speaks to—to put down her books and come outside, because there is "more of wisdom" in the songs of the birds outside than there is in any book. The speaker personifies the birds and even the sun, as if to convey the idea that everything in nature is purposeful and wise; the bird is not a "mean" preacher but a wise one, and the sun freshens the fields with "His first sweet evening yellow." Nature stands with her "ready wealth" to bless their hearts and minds, breathing truth with a cheerfulness not to be found elsewhere. Nature is the best teacher, far better than other people, and far better than books.

According to Wordsworth's speaker, nature can tell us "more of man" and more about good and evil than books written by "all the sages can." Books merely encourage our "meddling intellect," which misshapes and deforms all the beauty to be found in the world. The pages of books are like "barren leaves," dead rather than living, especially compared to the living leaves outside. Book learning, the speaker asserts, is not the most effective way to understand truth and beauty.

The speaker claims that "We murder to dissect" the things that we try to understand. In order to take them apart, we must first kill them—either literally or figuratively. This is what happens, the speaker says, when people study and read about something for too long, going over and over the material, trying to understand it fully: they end up "killing" the subject that they seek to understand. Rather than study the "barren leaves" of books that only contain dead things, it is best to go outside and experience the living natural world.