Humorous, Matter of Fact, Natural
You have to give Ursula Le Guin her props: even in a novel where billions of people are killed for the sake of a greater cause, she manages to make us laugh. In between all of the shifting realities, the drama, and the sadness, we get little nuggets of humor.
Try this example on for size:
So great a joy filled Orr that, among the forty-two persons who had been jamming into the car as he thought these things, the seven or eight pressed closest to him felt a slight but definite glow of benevolence or relief. The woman who had failed to get his strap handle away from him felt a blessed surcease of the sharp pain in her corn; the man squashed against him on the left thought suddenly of sunlight; the old man sitting crouched directly in front of him forgot, for a little, that he was hungry. (3.82)
We can't help but imagine this is a cartoon where George's glow of joy radiates off of him, shining on all of the other passengers like a halo. Thank goodness for passages like this, because otherwise this would be a very depressing novel, right?
The tone of The Lathe of Heaven doesn't call attention to itself. Even though Le Guin uses it to make us feel different emotions, it never gets in the way of enjoying the story. Actually, it helps us enjoy the story precisely because it doesn't give too much away.
The matter-of-fact tone helps create a feeling of surprise in us when we finally discover how George's dreams have transformed the world. Get a load of this, for example:
It was not until he had got off the subway at Ross Island Bridge West, and had walked up the hill several blocks and taken the elevator eighteen floors to his one-room 8-1/2 X 11 flat in the twenty-story independent-income steel-and- sleazy-concrete Corbett Condominium (Budget Living in Style Down Town!), and had put a soybean loaf slice in the infrabake, and had taken a beer out of the wallfridge, and had stood some while at his window—he paid double for an outside room— looking up at the West Hills of Portland crammed with huge glittering towers, heavy with lights and life, that he thought at last: Why didn't Dr. Haber tell me that he knows I dream effectively? (3.83)
In this passage, we discover that George's future is very different from our current life, but still, the tone never gets dramatic or sensational. Le Guin never up and says, "Wow, look how weird and futuristic this is!" It's just a matter of fact. It's normal and everyday for George, so that's how it's presented to us.
What, you mean to tell us that you don't love a toasty soybean loaf from your infrabake?