成唯識論演祕 2.289

2.289

如《疏》具簡真如等法不定失矣。有義：說因應云許是有為或無為不攝，非異色、心及諸心所作用可得，即簡不定。

As the Commentary fully qualifies, it avoids the inconclusive fallacy concerning true suchness and other dharmas. One interpretation holds: In stating the reason, one should say, 'Accepting that it is conditioned, or not subsumed under the unconditioned, no function can be apprehended that is distinct from form, mind, and the various mental factors'—this qualifies and eliminates inconclusiveness.