“Idea” is a pretty vague term, so we should begin by dividing the ideas into types: On the symbolic idea level, many readers see this poem as a comment on death and suicide, as though Frost was musing on whether the thought of death could be compared to a moment of quiet contemplation of ending our “journey” through the “night” of our cold and lonely existence. The extreme popularity of the poem, however, calls for a more thorough look at the poem’s “ideas.” It might merely be, on the social, human level, a poetic expression of our life, partly simply a fulfillment of prior commitments (“I have promises to keep”)—a sort of model of the momentum our lives have, through the “woods” of our environment—effort and rest, and the “getting through” our day. But the real value of the poem is the idea of its immediacy, its portrait of presence, of “being here now.” The narrator/traveler pauses a moment in the dark and looks around him or her at the landscape, devoid of all human contact, both quiet and still, and takes in the tranquility. The horse, ever a servant to its master’s command, has stopped its journey, for no discernable reason for a beast, and shakes its bells, an artificial noise that fills the void, unlike man, who throws the blanket of cause and effect over every decision to act or not act, but can “imagine” a pause in logical actions. The remarkable mood and atmosphere of the poem, embellished by the easy rhythms and smooth rhymes of the words, are alone the “idea” of this poem/scene, and could alone give the poem its reason for being, over and above any symbolic value.