The Middle Length Discourses of the Buddha - Bhikkhu Nanamoli [14]
The next stage in the sequence describes the attainment of the jhānas, profound states of concentration in which the mind becomes fully absorbed in its object. The Buddha enumerates four jhānas, named simply after their numerical position in the series, each more refined and elevated than its predecessor. The jhānas are always described by the same formulas, which in several suttas (MN 39, MN 77, MN 119) are augmented by similes of great beauty. Although in the Theravāda tradition the jhānas are not regarded as indispensable to the attainment of enlightenment, the Buddha invariably includes them in the full gradual training because of the contribution they make to the intrinsic perfection of the path and because the deep concentration they induce provides a solid base for the cultivation of insight. While still mundane the jhānas are the “footsteps of the Tathāgata” (MN 27.19–22) and foretokens of the bliss of Nibbāna that lies at the training’s end.
From the fourth jhāna three alternative lines of further development become possible. In a number of passages outside the sequence on the gradual training (MN 8, MN 25, MN 26, MN 66, etc.) the Buddha mentions four meditative states that continue the mental unification established by the jhānas. These states, described as “the liberations that are peaceful and immaterial,” are, like the jhānas, also mundane. Distinguished from the jhānas by their transcendence of the subtle mental image that forms the object in the jhānas, they are named after their own exalted objects: the base of infinite space, the base of infinite consciousness, the base of nothingness, and the base of neither-perception-nor-non-perception. In the Pali commentaries these states came to be called the immaterial or formless jhānas (arūpajjhāna).
A second line of development disclosed by the suttas is the acquisition of supernormal knowledge. The Buddha frequently mentions six types as a group, which come to be called the six kinds of direct knowledge (chaḷabhiññā; the expression does not occur in the Majjhima). The last of these, the knowledge of the destruction of the taints, is supramundane and thus properly belongs to the third line of development. But the other five are all mundane, products of the extraordinarily powerful degree of mental concentration achieved in the fourth jhāna: the supernormal powers, the divine ear, the ability to read the minds of others, the recollection of past lives, and the divine eye (MN 6, MN 73, MN 77, MN 108).
The jhānas and the mundane types of direct knowledge by themselves do not issue in enlightenment and liberation. As lofty and peaceful as these attainments are, they can only suppress the defilements that sustain the round of rebirths but cannot eradicate them. To uproot the defilements at the most fundamental level, and thereby yield the fruits of enlightenment and deliverance, the meditative process must be redirected along a third line of development, one which does not necessarily presuppose the former two. This is the contemplation of “things as they actually are,” which results in increasingly deeper insights into the nature of existence and culminates in the final goal, the attainment of arahantship.
This line of development is the one the Buddha pursues in the sequence on the gradual training, though he precedes it by descriptions of two of the direct knowledges, the recollection of past lives and the divine eye. The three together, which figured prominently in the Buddha’s own enlightenment (MN 4.27–30), are collectively called the three true knowledges (tevijjā). Although the first two among these are not essential to the realisation of arahantship, we may assume that the Buddha includes them here because they reveal the truly vast and profound dimensions of suffering in saṁsāra and thereby prepare the mind for the penetration of the Four Noble Truths, in which that suffering is diagnosed and surmounted.
The process of contemplation by which the meditator develops insight