首楞嚴義疏注經 9.57

9.57

此判成虛妄也。不了妄想體空，乃執生滅勞累，厭此生滅求不生滅，故云以生滅為因，捨生趣不生，未是真不生。見第六識暫爾不行，如氷夾魚，不知微細生滅，妄謂涅槃，非真涅槃也，故云不能發明無生滅性。初半劫下，却釋彼報行相。准《俱舍》引《婆沙》釋彼生死位，多時有想，初生此天，經於半劫，始入無想異熟，名初半劫滅。欲無常時，從異熟出，經半劫有心，後始方死，名後半劫生。生滅中間一向無想，名無想天。

This evaluates it as being false. Failing to understand that the essence of false thoughts is empty, they cling to arising and ceasing as tiresome, reviling this arising and ceasing to seek non-arising and non-ceasing; hence it is said, 'takes arising and ceasing as the cause.' Casting off arising to head toward non-arising is not yet true non-arising. Seeing that the sixth consciousness temporarily does not function, like a fish encased in ice, and unaware of subtle arising and ceasing, they falsely call it nirvāṇa, but it is not true nirvāṇa; hence it is said, 'they cannot illuminate the nature of non-arising and non-ceasing.' 'During the first half-kalpa' onward conversely explains the aspects of their retribution. In accordance with the *Kośa* citing the *Vibhāṣā* to explain the state of birth and death therein: for most of the time there is thought; when first born into this heaven, after half a kalpa, one first enters the vipāka of non-thought, which is called 'during the first half-kalpa it is extinguished.' When about to be impermanent [at death], one emerges from the vipāka, having a mind for half a kalpa, and only then dies, which is called 'during the second half-kalpa it arises.' Between arising and ceasing it is entirely without thought, so it is called the Heaven Without Thought.