Why Is There the Misunderstanding of Not Distinguishing Truth from Falsehood?

A person's thoughts are the notions and views formed by the mind consciousness through mental activities such as discrimination, analysis, judgment, deliberation, reasoning, and comparison. The nature of the mind consciousness can be coarse or subtle; when it is subtle, it is very difficult for us to detect it ourselves. Many times, the mind consciousness is operating moment by moment, constantly knowing and perceiving; only when consciousness has ceased does it stop functioning and lose its discriminating nature. At all other times, as long as consciousness exists, it is discriminating the mental sense-objects (dharma-objects), yet we ourselves are unable to introspect and perceive this. Why can we not introspect and perceive it? Because our wisdom is insufficient and our meditative concentration (samādhi) is not fully developed.

When one cannot introspect and perceive that the mind consciousness is discriminating the mental sense-objects, some people claim that they have reached a state of no-mind, or that they have become thought-free; others say that they have realized the true mind which is free of both delusive thoughts and conceptualization—but this is a tremendous misunderstanding. This is a clear case of failing to distinguish the true from the false, showing that they have not understood the Heart Sutra at all. The Heart Sutra says that the true mind neither arises nor ceases, yet such a person takes the mind consciousness—which had delusive thoughts and has now become free of delusive thoughts—to be the true mind. This so-called true mind is in fact a conditioned phenomenon subject to arising and ceasing: when delusive thoughts are present, this "true mind" does not exist; when delusive thoughts are absent, this "true mind" appears again. This is completely not the true mind that the Buddha spoke of.