Why doesn't the mother know what the noise is in "The Rocking-Horse Winner"?
She stood, with arrested muscles, outside his door, listening. There was a strange heavy and yet not loud noise. Her heart stool still. It was a soundless noise, yet rushing and powerful. Something huge, in violent, hushed motion. What was it? What in God's name was it? She ought to know. She felt that she knew the noise. She knew what is was. (Lawrence 147)
In D.H. Lawrences' "The Rocking-Horse Winner," the sound that the mother hears but can't recognize is the rocking of her son on his wooden horse. This is significant because it shows the kind of mother she is: if Paul's mother spent more time with her son, she would know the sound instantly.
Throughout the story, all Paul's mother cares about is having more money. Even the house whispers, "There must be more money! There must be more money!" Like any child sensitive to the worries and fears of his parent, and Paul feels the pressure (and he hears the house whisper). Soon he discovers that he can make money by betting on horse races—while he rides his rocking-horse to guarantee that his horse wins. With the help of Bassett, the family's gardener, and Paul's Uncle Oscar, Paul is able to place bets and collect the winnings.
With Oscar's help, Paul anonymously gives a large sum of cash to his mother, and though the money should satisfy her—and the whispering of the house—it does not.
We can see how Paul's mother values wealth. When Paul first gives her a thousand pounds (with the promise of another thousand on her birthday for the next four years), it should ease her worry, but in her foolish obeisance and idolatry of money, his mother is ungrateful—the present is "quite moderately nice," she says...
...her voice cold and absent.
Paul, so anxious to please his mother, gives his mother the "whole five thousand at once," and the feeling that comes over the house is much like the craziness that takes hold of Paul later. The voices go...
...mad, like a chorus of frogs on a spring evening.
Later, as the money is spent, the voices...
...trilled and screamed in a sort of ecstasy.
Paul knows that the most important race (the Derby) is coming up, and he must be able to ride. His mother's parenting instincts try to speak out over her desire for more money, but instead of listening to her uneasy feelings about Paul, she goes to a party—this takes place two days from the Derby. The quote referenced above describes the sound that Paul's mother hears from his room when she returns.
Agitated beyond words, pool Paul is racing on his horse. He is driven by his mother's anxiety for money, but that desire has become "rushing and powerful," "huge, in violent, hushed motion." The need is out of control. On the other side of the door, the noise "goes on and on…like a madness." When Paul's mother opens the door…
The room was dark. Yet in the space near the window, she heard and saw something plunging to and fro. She gazed in fear and amazement.
…her son…was madly surging on the rocking-horse.
Paul's mother fails to understand the needs of her son, seeing only what she wants. She forgets that before all else, she should be the loving parent. It is only as Paul goes still and crashes to the floor that "all her tormented motherhood" rushes over the boy's mother. It is, of course, too late. In several days, though Paul learns that their horse has won, he dies. Oscar chastises his sister on creating an environment that required so much of the boy that while gaining money for his mother, he lost his life. Uncle Oscar's well-known line closes the story...
…he's best gone out of a life where he rides his rocking-horse to find a winner
…because for Paul's mother, her son and all that she had in life didn't satisfy her. The winners Paul finds are the horses—for Paul feels he is not important enough to be a winner in her eyes, just for who he is.