Why Can't One Mind Be Used for Two Things?

Question: As the common saying goes, "one mind cannot attend to two things at once" — this refers to the mind consciousness, which cannot think about or carry out two things simultaneously. But the manas pervasively attends to all dharmas, or before it has finished attending to one dharma, it attends to another; since the interval is as short as a kṣaṇa, it can also be understood as attending to multiple dharmas simultaneously. Within this, is it a good opportunity to distinguish between the mind consciousness and the manas?

Answer: The worldly saying that one mind cannot attend to two things means that if one mind is used for two or more purposes, the application will not be good: energy is scattered, the mind becomes coarse, discernment is not fine or clear, thinking is not clear, and wisdom cannot arise. In fact, the mind consciousness and the six consciousnesses can attend to two things and three things at once. Because ordinary people have very poor meditative concentration and also very poor power of wisdom, once their energy is slightly scattered, their discernment of the six sense objects becomes unclear, their consideration of problems is not meticulous or thorough, manifesting as carelessness, sloppiness, muddled confusion, not knowing why things are so — their wisdom is rather inferior.

When the mind consciousness has not been trained, in order to deliberate and consider something well, it must think with single-minded focus; otherwise it cannot consider things clearly. When the mind consciousness has been trained and its meditative concentration is good, it can attend to multiple things with one mind, attending to several dharmas simultaneously and doing all of them well. For example, the worldly saying "eyes observing six directions, ears listening to eight quarters" is just like this — only one cannot engage in very fine deliberation, yet everything can be arranged well on the whole. For instance, some people, when a major event is upon them, often appear very calm; at that time all their energy and abilities are mobilized and brought into play, all matters are considered and arranged very thoroughly, the brain spins at high speed, and the speed of work is astonishing. Worldly people at work are sometimes like this too; each person's energy and abilities differ greatly, and their concentration and wisdom also differ.

The manas can attend to multiple dharmas simultaneously, and it can also attend to multiple dharmas in continuous succession, moment after moment without interruption. If He is to attend to dharmas among the six sense objects, the mind consciousness will inevitably discern them accordingly, so the mind consciousness can also attend to multiple dharmas. To distinguish the mind consciousness from the manas, it is still easier to distinguish them in terms of the nature of being the master and in making decisions; they are easy to distinguish in terms of habitual tendencies, inertia, and functions. When something happens suddenly, it is easy to distinguish the functions of the mind consciousness and the manas; and it is relatively easy to distinguish the mind consciousness and the manas by comparing shallow-level psychological functions with deep-level psychological functions.