The tone in Thanatopsis reflects the narrator's attitude toward the topic. Tone is made more intricate because the narrator ceases to speak for himself and begins to speak for Nature ("Comes a still voice--"). There are many mood shifts as the speaker in Thanatopsis shifts and as the discussion shifts. Overall, the ultimate tone would be drawn from the final set-off stanza ("So live, that when thy summons comes to join"), which represents the last tone shift, and would be summed up as soothing, comforting and uplifting, though the major portion is in Nature's voice and is illuminating and factual.
Prior tones, at previous tonal shifts, are casual and informing ("To him who in the love of Nature holds"); sad and eerie ("...and she glides / Into his darker musings,"); illuminating and factual ("Go forth under the open sky,"); somber ("...yet the dead are there:"); sad but factual ("...and what if thou withdraw / In silence..."); hauntingly final ("As the long train / Of ages glide away,"); soothing and uplifting ("So live, that when thy summons comes to join").
Tone is defined as the speaker's or narrator's voice (or tone of voice). The tone establishes the emotional intent of the poet or author and is delivered by the speaker or narrator and produces the emotional quality of the poem or narrative. Tone differs from mood because tone is conveyed through language alone while mood is conveyed through setting, objects, images, details and words.