Both of these excellent poems explore the compulsive need that man has to search for meaning and seek significance in his own existence. In "A Noiseless Patient Spider," for example, the sight of a spider throwing out filaments to try and connect it to something stable becomes a powerful metaphor for the human soul and its desire to find something strong to connect itself to:
And you, O my Soul, where you stand,
Surrounded, surrounded, in measureless oceans of space,
Ceaselessly musing, venturing, throwing--seeking the spheres, to connect them...
In this image of life, the soul's only task and job is "musing, venturing, throwing" without end, always seeking to connect "the spheres" of existence and find meaning in "measureless oceans of space" that threaten to render it insignificant and unconnected.
In "Facing West from California's Shores," the speaker has returned from seeing the world, "Inquiring, tireless, seeking what is yet unfound," only to recognise that through ceaselessly embarking on this quest for meaning, he has actually not found what he was looking for in the first place:
...round the earth having wander'd,
Now I face home again—very pleas'd and joyous;
(But where is what I started for, so long ago?)
The question that ends the poem gives it a tone of doubt as if the actual exercise of endlessly voyaging across the globe has been nothing more than a distraction to the real quest, which was to find some sense of significance.
Both poems therefore present the search for meaning in life as being something that is intrinsic to us and something that comes naturally to us as breathing does. However, it also suggests that meaning is an ongoing quest; we will never "arrive" at understanding our own significance and we will continue to search for that significance our entire lives.