As the poem opens, the elderly Ulysses—his many adventures seemingly behind him—feels old and useless in old age. As he puts it,

How dull it is to pause, to make an end,
To rust unburnish'd, not to shine in use!

Ulysses also calls it "vile" to be accomplishing nothing and simply sitting around remembering the glory days when he was a warrior or roaming on the high seas. His "gray" or elderly spirit is still filled with the yearning to achieve new things and travel far and wide. When the poem opens, Ulysses has fallen prey to the idea that an older person is past his prime. As the poem progresses, though, he comes to know that (though his body might be weaker) he still has much to offer and experience.

Ulysses, pondering his own idleness, watches his son Telemachus, whom he believes will be a capable ruler once he leaves his throne. Telemachus's "slow prudence" and sense of decency suit him to serve as a ruler and stay close to home, while Ulysses is suited to explore. Ulysses appreciates his son's skills but notes that he and Telemachus are called to different tasks. As Ulysses states, "He works his work, I mine." Ulysses is wise to note that we are not all the same and to accept his own role in life, as well as his son's.

We should not, the poem implies, let age hold us back. By the end of the poem, Ulysses realizes that he has to be true to himself and not let his own ideas of age keep him at home, even though he strove for home for so long. He is meant to explore and pursue adventure, and that is what he resolves to do. He states,

'T is not too late to seek a newer world.

Ulysses expresses the idea that life isn't over until it is over and that, in the meantime, we should do what we are called to do—we must not give up. He feels he can go on one more adventure, stating that old age still has a sense of "honor" and a desire to "toil" that can't be repressed. Those who are older have lost much, Ulysses acknowledges, but still hold the essence of what makes them individual: that is, the commitment to act unrelentingly, to do what they must while they still live.