Linji is best known for his use of the shout. He shared the concern of Huangbo and Mazu with the problem of wordless transmission and to their repertory of beatings and silences he added the yell, another way to affirm insights that cannot be reasoned. We may speculate that the shout was rather like a watered-down version of the beating, requiring less effort but still able to startle at a critical instant. He seems to have been particularly fond of classifying things into groups of four, and one of his most famous classifications was of the shout itself:
The Master to a monk: "Sometimes a shout is like the jeweled sword of a spirit King [i.e., extremely hard and durable]; sometimes a shout is like the golden-haired lion crouching on the ground [i.e., strong, taut, and powerful]; sometimes a shout is like a weed-tipped fishing pole [i.e., probing and attracting the unwary]; and sometimes a Shout doesn't function as a shout. How do you understand this?"
As the monk fumbled for an answer, Linji gave a shout.
His philosophy of the shout as a device for cutting off sequential reasoning was thus demonstrated by example. But the question those who relate this story never resolve is: Which of the four shouts was the shout he used on the student? (John Wu in The Golden Age of Zen speculates that this shout was of the first category, since it was meant to "cut off" the monk's sequential thought, but that seems a rather simplistic mixing of-the metaphorical with the concrete.)