The Middle Length Discourses of the Buddha - Bhikkhu Nanamoli [16]
Whereas in serenity meditation the meditator attempts to focus upon a single uniform object abstracted from actual experience, in insight meditation the endeavour is made to contemplate, from a position of detached observation, the ever-shifting flux of experience itself in order to penetrate through to the essential nature of bodily and mental phenomena. The Buddha teaches that the craving and clinging that hold us in bondage are sustained by a network of “conceivings” (maññita)—deluded views, conceits, and suppositions that the mind fabricates by an internal process of mental commentary or “proliferation” (papañca) and then projects out upon the world, taking them to possess objective validity. The task of insight meditation is to sever our attachments by enabling us to pierce through this net of conceptual projections in order to see things as they really are.
To see things as they really are means to see them in terms of the three characteristics—as impermanent, as painful or suffering, and as not self. Since the three characteristics are closely interlinked, any one of them can be made the main portal for entering the domain of insight, but the Buddha’s usual approach is to show all three together—impermanence implying suffering and the two in conjunction implying the absence of self. When the noble disciple sees all the factors of being as stamped with these three marks, he no longer identifies with them, no longer appropriates them by taking them to be mine, I, or self. Seeing thus, he becomes disenchanted with all formations. When he becomes disenchanted, his lust and attachment fade away and his mind is liberated from the taints.
Instructions for the development of insight in the Majjhima Nikāya, though concise, are many and diverse. The single most important lesson on the practice conducing to insight is the Satipaṭṭhāna Sutta, the Discourse on the Foundations of Mindfulness (MN 10; also found in the Dīgha Nikāya with an amplified section on the Four Noble Truths). The sutta sets forth a comprehensive system called satipaṭṭhāna designed to train the mind to see with microscopic precision the true nature of the body, feelings, states of mind, and mental objects. The system is sometimes taken to be the paradigm for the practice of “bare insight”—the direct contemplation of mental and bodily phenomena without a prior foundation of jhāna—and, while several exercises described in the sutta can also lead to the jhānas, the arousing of insight is clearly the intent of the method.
Other suttas in the Majjhima Nikāya describe approaches to developing insight that either elaborate upon the satipaṭṭhāna contemplations or reach them from a different starting point. Thus MN 118 shows how the practice of mindfulness of breathing fulfils all four foundations of mindfulness, not the first alone as shown in MN 10. Several suttas—MN 28, MN 62, MN 140—present more detailed instructions on the contemplation of the elements. MN 37, MN 74, and MN 140 contain illuminating passages on the contemplation of feeling. In some suttas the Buddha uses the five aggregates as the groundwork for insight contemplation (e.g., MN 22, MN 109); in some, the six sense bases (e.g., MN 137, MN 148, MN 149); in some, the two combined (MN 147). MN 112 has sections dealing with insight based on the five aggregates, the six elements, and the six sense bases, and as resulting from the gradual training. MN 52 and MN 64 show that insight can also be aroused with the jhānas, the immaterial attainments, and the divine abodes as its objects: the disciple enters any of these states and contemplates its constituent factors as subject to the three characteristics.
Several sequences of meditative states mentioned in the Majjhima culminate in an attainment called the cessation of perception and feeling (saññāvedayitanirodha).