What does it mean that the true mind is neither lost nor gained?

The true mind cannot be obtained, nor can it be lost. What does "neither lost nor obtained" mean? It means neither arising nor ceasing. Because it does not arise, it is not obtained—it exists inherently from the beginning; because it does not cease, there is no need for it to arise, and thus there is nothing to obtain. The true mind itself is an unconditioned dharma (asaṃskṛta-dharma); there is no need to attain it. An unconditioned dharma that is cultivated through practice will also have a time of ceasing—it is a conditioned dharma subject to arising and ceasing. The unconditioned suchness of true thusness neither arises nor ceases, accompanying the tathāgatagarbha like a shadow following its form. The tathāgatagarbha is formless and without marks; between them there is mutual containment, yet even this containment bears no mark of containing—they simply do not repel one another, but cooperate with each other, jointly accomplishing all dharmas. It is the same with the Buddha's tathāgatagarbha and sentient beings' tathāgatagarbha: they also cooperate with one another. Therefore, the tathāgatagarbha of sentient beings need not merge into the Buddha's tathāgatagarbha; the tathāgatagarbha is not material form (rūpa), having neither inside nor outside, so they cannot enter into one another. Only material form can merge into and enter other material form.