俱舍論記 4.163

4.163

「此二體類至顯其別相」者，毘婆沙師答。尋、伺體類別相難說，但由上麁下細顯其別相。

"The distinct characteristics of the substances and classes of these two ... manifest their distinct characteristics": The Vaibhāṣika answers. The distinct characteristics of the substances and classes of vitarka and vicāra are difficult to express; their distinct characteristics are merely manifested through the superior being coarse and the inferior being fine.