Only by knowing how to practice and investigate can one achieve results.

Cultivating meditative concentration ensures that deliberation and contemplative practice (vipaśyanā-caryā) and investigation can proceed; otherwise, the mind becomes scattered after only a brief period of deliberation. Without meditative concentration (dhyāna), deliberation has no thread to follow, and one's thinking is not clear.

The process of applying effort in investigation is extremely complex; the mental activities of the mind consciousness and the manas are very deep and subtle. If it is not handled well and one does not know how to apply effort, investigation will yield no result. One must know how to use effort—once the mental activities within are clearly understood, one will know how to direct the mind and how to apply effort.

When the mind consciousness and the manas investigate together, the five sense consciousnesses also play a certain role. Otherwise, one would be in the state of the second dhyāna, where the five sense consciousnesses are absent; in that case there would be no deliberation or contemplative practice, and enlightenment would be impossible. The tathāgatagarbha also plays a corresponding role in this process; otherwise, there would be no seven consciousnesses.