俱舍論記 23.22

23.22

「此四念住至不增不減」者，釋第八句，明唯有四。四念住中，觀身不淨治彼淨倒，觀受是苦治彼樂倒，觀心無常治彼常倒，觀法無我治彼我倒。又《正理》云「或為對治段、觸、識、思食，如次建立身等四念住，故唯有四不增不減。」

"These four applications of mindfulness ... neither increase nor decrease": this explains the eighth line, clarifying that there are only four. Among the four applications of mindfulness: contemplating the body as impure counters the distortion of purity; contemplating feeling as suffering counters the distortion of pleasure; contemplating the mind as impermanent counters the distortion of permanence; contemplating dharmas as non-self counters the distortion of self. Furthermore, the Nyāyānusāra states: "Alternatively, to counter the foods of morsel, contact, consciousness, and mental volition, the four applications of mindfulness on body and so forth are established in that order; hence there are only four, neither increasing nor decreasing."