Not living for each other's sake,The poem has a zenlike quality about it, and I can imagine a professor in an epistemology course spending a class or two trying to unravel what it means, if anything.
Mind and the world will rarely rime;
The raindrops aiming at the lake
Are right on target every time.
The brain evolved to make sense of the world, so I suspect that mind and world will rhyme more often than Nemerov supposes (I change his spelling). The fact that we can send a spacecraft across hundreds of millions of miles of interplanetary space and have it land on a dime is an impressive rhyme.
The last two lines of the poem are rather more cryptic. The poet seems to be suggesting that the world is so big and various and human knowing so fractional and stuttering that it is hard to say anything that isn't in some sense true. I'd say that the spacecraft that plops down on target on a distant moon is more like a raindrop aiming at a dime.
Surely, the world does not live for our sake, but maybe we live for the world's sake. Our minds rhyme with the world for the same reason our bodies evolved, say, a circadian rhythm. We should take Nemerov's little poem to heart, but it is the whole point of science to narrow the target of the raindrop, and to sharpen the rhyme between knowledge and the world.