The poem begins with a wish: not to let a certain feeling be lost, or perhaps not to let it be disturbed. The speaker pictures silverfish skittering across a pond, moving over the surface while the reflected sky and trees stay intact. That image becomes a way of describing the mind, which can take in the world like water without breaking it.
The speaker then turns to someone addressed as "you," presumably Doris, and says that an idea which struck her also struck him: the mind as a mirror of the world. It offers "a way out of unhappiness," but the speaker is careful to say this isn't the same as being happy in the everyday, exclaiming sense. It is quieter, a depth rather than a mood. What it holds are "the various possibilities," including both faces, yours and mine. The last word, "tendered, tended," suggests offering and care. The mood is calm, tender and shared, with a gentle hope that attention can be a kind of comfort.