The theme of the poem revolves around reflection on the passage of time and the interplay between memory, loss, and the anticipation of an uncertain future. The speaker contemplates their experiences and the beauty of the past while also acknowledging the inevitability of change and the things they will never witness.
An example of a sentence from the poem that develops this theme is: "For still there are so many things that I have never seen." This line encapsulates the sense of longing and the awareness of missed experiences, contributing to the overall tone of reflection and introspection.