The Structure of Matter and the Universe
Buddhism’s view of the universe has undergone many changes over the last 2,500 years. Very broadly, we can divide Buddhist cosmology into two streams, Abhidharma and Mahayana. About a hundred years after Sakyamuni’s death in the fourth or fifth century B.C.E., Buddhism split into two schools, and in the following two or three hundred years these divided further into eighteen or twenty schools, which are collectively called Abhidharma Buddhism. Around the first century B.C.E. a movement to restore the original spirit of Buddhism arose in reaction to Abhidharma Buddhism, which had become formalized and academic. The reformers called their form of Buddhism Mahayana (“great vehicle”) and labeled Abhidharma Buddhism Hinayana (“small or lesser vehicle”). Toward the end of the Mahayana period, esoteric or Tantric Buddhism made its appearance, and this form of Buddhism also had its distinctive view of the universe. In this book, though, I deal only with the Hinayana and Mahayana traditions.
Buddhist cosmology according to the Hinayana tradition centers on (1) the realm of Mount Sumeru, (2) dharmas (the Buddha’s teachings), and (3) the notion that the Buddha (Sakyamuni) is a historical person. In Mahayana Buddhism, (1) the various “buddha-realms” are more prominent than Mount Sumeru, (2) the Buddha (or buddhas) takes precedence over dharmas, and (3) the Buddha is a suprahuman (cosmological) existence. As we shall see in part 2, Mahayana views thus changed Buddhism from a philosophy to a religion.
I have relied principally on Vasubandhu’s Abhidharmakosa (Abhidharma storehouse treatise) for my description of preMahayana cosmology which makes up part 1 of this book. This work, dating from the fifth century C.E., contains an excellent and concise description of the Buddhist view of the cosmos.1 For my treatment of Mahayana cosmology in part 2,1 have depended chiefly on the Flower Garland Sutra (ca. 3d century C.E.) and the Larger Sukhavatl-vyuha (ca. 2d century C.E.). Though the Abhidharmakosa dates from the fifth century, it inherits a doctrinal stance that predates the common era, so we can say that both the Flower Garland Sutra and the Larger Sukhdvati-vyuha actually postdate the Abhidharmakosa in terms of doctrinal development.
Basic Components of Matter
The smallest particles. Just as the modern scientific view of the cosmos is based on atomic theory, Buddhism posits elements and atoms along with its theory of the universe’s structure. The fifth-century Abhidharmakosa examines elements and atoms in a chapter entitled “Analyzing the world [[[dhatu]]).” Let us look at how the Abhidharmakosa treats the subject and supplement the explanation using the Great Commentary (Abhidharma-maha-vibhasa-sastra, ca. 100-150 C.E.), an encyclopedia of the thought of the Sarvastivadins (one of the twenty Hinayana schools), of which the Abhidharmakosa is a compendium.
These Buddhist texts discuss particles called atoms (paramanus), defined as “the smallest part of matter, uncuttable, unable to be destroyed, taken up, or grasped. They are neither long nor short, neither square nor round. They cannot be analyzed, seen, heard, or touched.”2 Paramanu derives from parama (“extreme”) and anu (“minute”). This definition reminds us of the Greek atomos (“atom”), made up of a (“not”) and tomos (“cut”).
Paramanus cannot exist individually; only when many paramanus accumulate can they occupy space and undergo change.
According to the Abhidharmakosa, in the first step of this process, one of seven paramanus becomes the nucleus around which the other six spread themselves three-dimensionally, making one molecule (anu; see figure 1). However, according to the Vaise-sika school of thought (one of the six principal Brahmanical, or orthodox Hindu philosophies), matter becomes visible as follows. Two paramanus make a molecule, a particle called a diyanuka. Three such dtyanukas join to make a tryanuka, which is the size of a trasarenu, a dust mote visible in the rays of the sun. Four tryanukas make a caturanuka (see figure 2). Thus larger and larger particles form, eventually creating matter that we are able to perceive. This process occurs by means of the power of adrsta, “invisible force.”
All matter is said to be made up of the “four great elements” (catvari maha-hhutam): earth, water, fire, and wind. Whereas the paramanus are matter, the four great elements seem to be energy. They are not the physical earth, water, fire, and wind that we see or feel around us; they are invisible, though they do occupy space. As energy, the four great elements constitute paramanus, and it is only when numbers of paramanus congregate that we are able to perceive earth, water, fire, or wind themselves, or any other matter that exists.
Each element has special characteristics and functions: earth is solid and supports things; water is moist and dissolves things; fire is hot and boils things; and wind is mobile and causes things to grow. (Wind, consisting of air, was believed to be like breath, and therefore it was thought to cause growth or at least to maintain existence.) The elements do not exhibit their presence equally in all types of matter. Some particular elements are abundant in one thing; other elements are abundant in another thing. That is why some matter is solid, some pliant, some moist, and some hot. Another explanation has it that in any matter, the four elements are equally mixed and that only a particular element among them has the power to determine the characteristics of that matter.
Greek atomism. What is the origin of Indian atomic theory? According to Buddhist sources, the theory of the elements was expounded by Ajita Kesakambalin and Pakudha Kaccayana, two philosophers who were active in India at the same time as Sakyamuni Buddha (ca. 560-ca. 480 b.c.e. or ca. 460-ca. 380 B.C.E.). Ajita taught that only the four elements—earth, water, fire, and wind—have true reality, being independent and immutable. Human beings are composed of these four elements, and when they die, the earth part of their composition returns to join the earth in the world, as do the water, fire, and wind parts to the water, fire, and wind in the world. The faculties of the various organs return to empty space. Pakudha taught the existence of seven elements, adding suffering, pleasure, and the life force to the above four. “There is neither the killer nor the killed. . . . Even if [someone] cuts off the head with a sharp sword, no one takes the life of any other [because] the sword only passes through the spaces of the seven elements.”3
Several other Indian schools of philosophy also have such theories. For example, the Vaisesika school, the oldest of the six orthodox Hindu philosophical systems, declares that atoms are not infinitely small, for if they were, both Mount Sumeru (the enormous mountain thought to be the center of the universe) and a mustard seed would be made up of an infinite number of atoms and therefore be of the same size?
There is also a strong possibility that Greek philosophy influenced Indian atomic theories. In the fifth century B.C.E., Empedocles suggested that the four elements—water, air, fire, and earth—were the primary constituents of the universe, and Democritus posited the existence of atoms. Aristotle (384—22 B.C.E.) accepted the theory of the elements and assigned them particular characteristics (see figure 3).
It appears that, chronologically, the Indians were slightly in advance of the Greeks regarding the theory of the elements. Still, the Buddhist sutras were composed over a long span of time, and many new materials were added to the texts before they took their final written form. If we consider that the texts under discussion, and the Vaisesika works as well, took their permanent form some time after the fourth century B.C.E., then the theory of the elements might very well have come to India from Greece. The many points of similarity between the Greek and Indian theories are obvious, as is an overall agreement despite some differences in individual items.
One final point illustrates the possible Greek origin of Buddhist atomic theories. A fifth element, space (akasa), was eventually added to Buddhism’s four great elements. In esoteric Buddhism, the five great elements, like the five seed words, five shapes, and five bodily constituents, symbolized the essence of the universe, in a way analogous to the Chinese theory of five elements (wu-hsing; see figure 4). Democritus also wrote of space, not as a separate element, but as the location in which the four elements acted. In the fact that the Buddhists actually made space a fifth element, and that it seems to be qualitatively the same as the other four, we can conjecture that they copied Greek philosophy but erred in interpretation. Later chapters in this book discuss other Greek influences on Indian thought, and routes and sites of cultural exchange.
The Universe
In Buddhism, the common Sanskrit term for “universe” is loka-dhatu. It refers to a place that has come into existence through the karma (actions and their enduring results) produced by living beings. The universe is also maintained by karma and disintegrates through the action of karma. In later Buddhism, beginning in the second or third century, it was believed that the loka-dhatu existed within the human mind. The term universe came to have such a strong connotation of human life and destiny that it almost ceased to connote the universe as a spatial entity.
The Abhidharmakosa describes the universe as follows. A circle of wind (vayumandala} floats in space (akasdy This wind circle is disk-shaped, W9 yojanas in circumference and 1,600,000 yojanas in depth. (There are various explanations concerning the length of ayojana; one says it is about seven kilometers.) Resting on the wind circle is a disk of water (jalamandaldy, it has a diameter of 1,203,450yojanas and a depth of 800,000yojanas. Above the water circle is a disk-shaped layer of golden earth {kdhcanamandala), of the same diameter and 320,000 yojanas in depth. Its upper surface supports mountains, seas, and islands. To visualize the composition more easily, imagine a basin (the water circle) placed on top of a washtub (the wind circle), with a birthday cake (the golden earth circle with mountains) surmounting it.
The diameters of the water and golden earth layers are the same, because these two layers were originally a single layer, or more correctly a cylinder, of water only. The golden earth layer was formed as skin forms on the surface of boiling milk. The borderline between the two layers is called the golden ring extremity, an expression which has come to mean “the bottom-most place.” For humans, who live in one small section on top of the golden earth layer, the golden ring extremity is certainly the very bottom of the world.
Mount Sumeru. There are nine mountain ranges on the surface of the golden earth layer. Towering in the very center is Mount Sumeru, with seven ranges forming concentric squares around it. Proceeding outward, the seven ranges are called Yugan -dhara, Isadhara, Khadiraka, Sudarsana, Asvakarna, Vinataka, and Nimindhara.5 Beyond Nimindhara are four landmasses, spoken of as islands or continents. They are named Purvavideha (from purva, “east”) to the east of Sumeru, Aparagodanlya (from apara, “west”) to the west, and Uttarakuru (from uttara, “north”) to the north. In the case of Jambudvipa, the southern landmass, the prefix daksina, “south,” is omitted. On the perimeter of the golden earth layer is a circular range of iron mountains called Cakravada, which prevents the waters of the great sea containing the four landmasses from falling into the void. The other seven ranges are made of gold, and Sumeru, in the center, is made of the four treasures: gold on its northern face, silver on its eastern face, lapis lazuli on its southern face, and crystal on its western face. Because Jambudvipa is south of Mount Sumeru, its sky is blue, reflecting the lapis lazuli of the southern face. The mountains and landmasses penetrate the waters (see figure 5).
Many traditional representations of Mount Sumeru portray the seven mountain ranges as arranged in concentric circles, but according to the Abhidharmakosa, they are squares, with sides of 80,000 tyojanas each (see figure 6). A cross-sectional view shows the waters of the various seas as having a uniform depth of 80,000 yojanas, about 560,000 kilometers. This vastly surpasses the deepest known part of our oceans, the Mariana Trench, some 10 kilometers deep. Sumeru has a height of 160,000 yojanas, of which half is under water. The half above water is therefore 80,000 jojanas high. The heights above sea level of the eight ranges surrounding Sumeru are halved progressively from innermost to outermost.
So far, it has been easy to grasp the surface configuration of the golden earth layer. Two variables now complicate the matter. First, the width of each mountain range equals its height above sea level, which means that the width of each range is only half the width of the next range inward. Second, the widths of the seas also decrease progressively by half. The outermost sea, that between Nimindhara and Cakravada, is very wide, however, as shown in figure 7.6
Mount Sumeru, with a height of some 560,000 kilometers, is far taller than the tallest mountain in the Himalayas. The name Sumeru (sometimes Sumeru) recalls Sumer (or Shumer), the center of an ancient Mesopotamian civilization. The similarity in names seems to be no more than a coincidence, however.
The earliest appearance of the mountain’s name in literature is in the Mahabharata, the great Indian epic composed between the fourth century B.C.E. and the fourth century C.E., where it is called Meru. Buddhism no doubt adopted the name from that source. By adding the eulogistic Indo-Aryan prefix su- (“wonderful”), we get Sumeru.7
P. B. Spooner links Meru to Merv—not the town of Merv in Turkmeniya, but the Merv near Persepolis in Iran, a sacred mountain associated with the rise of the Achaemenid empire in the seventh century B.C.E. He also points out that the number thirty-three, in the heaven of the thirty-three gods on Sumeru’s summit, is Zoroastrian, from Persia.8 The invading forces of Alexander the Great (ca. 330 B.C.E.) heard the name Melos (Menis), and thought it had its origins in the thigh (melos) of Zeus.9 In addition, there seems to be a lingering tradition or memory of life at higher latitudes when we consider that the sun, moon, and stars revolve on a horizontal plane around Mount Sumeru (see figure 8). This reminds us that one theory has the Indo-Aryans coming from the direction of Russia, and that the northern land of Uttarakuru was considered a utopia.'0
All the same, there is a strong likelihood that the idea of the Mount Sumeru world originated not from geographical or historical reality but from the ancient Indian idea of a world axis. Mount Sumeru is the pillar that stands in the center of the world. When we add the wind layer below it and the heavens above it, we can see that this pillar penetrates the universe from top to bottom. The four directions are located with the pillar as center. The Indian liking for symmetry may have been a natural outgrowth of this concept of the directions.
P. Mus has argued that the stupa (the dome-shaped Buddhist shrine) incorporates and expresses the Mount Sumeru world. The hemispherical dome (anda) covers the whole structure. The cattravall, a series of parasols on the top, represents the various heavens of the realm of form, and the harmika, the square pavilion surmounting the dome, represents the heaven of the thirty-three gods. The pole (yasti) fixed to the harmika and supporting he series of parasols is the world axis. The four gateways (torana) on the north, south, east, and west sides of Stupa 1 at Sanci, India (see photo 1 and figure 9) express the Indian idea of direction." Archaeological investigations have revealed that this stupa’s foundation has the form of a spoked wheel (see figure 10). This may be no more than a simple structural feature, inasmuch as it was not visible once the stupa had been completed. All the same, the idea of the world axis and the directions may have played a part in its adoption. The spoked wheel was also used to represent the Wheel of the Dharma, possibly derived from the spokes of a chariot wheel or the sun’s disk, and also perhaps related to the concept of direction.12
The Indian subcontinent. Of the eight seas separating the mountain ranges, the inner seven are freshwater, but the vast outermost sea is of salt water. The four landmasses, each of different size and shape, are found in this large outer sea. Purvavideha, in the east, is shaped like a half-moon (though four sides are attributed to it). The curved side faces outward, and three sides measure 2,000 yojanas each whereas the fourth is only 350 yojanas. Jambudvipa, in the south, is a trapezoid, the short side facing outward. In fact, it is virtually a triangle. It has three sides of 2,000 yojanas each; the short side is 3.5 yojanas. Aparagodaniya, in the west, is a circle with a diameter of 2,500 yojanas. Uttarakuru, in the north, is a square, each side measuring 2,000 yojanas.
The southern land of Jambudvipa is “our” world. Figure 11 makes it obvious that this continent’s shape closely resembles the Indian subcontinent. Its various features bear this out; Jambudvipa’s characteristics correspond to the Indians’ geographical knowledge. For instance, in the northern part is a mountain range called Himavat, “mountains of snow.” These are the Himalayas (hima, “snow,” and alaya, “store”).
Modern Indologists, finding that the Abhidharmakosa locates Lake Anavatapta (“no heat or fever”) north of Himavat, searched for such a lake on existing maps. A clue to its location is that it was considered the common source of four great rivers, the Ganges, Indus, Oxus, and Sita. Modern maps do not show these four rivers flowing from the same source. If, however, we extend the upper reaches of each of the four rivers, they would meet more or less where there actually is a large lake. This is Manasarowar (Mapam in Tibetan), 4,602 meters above sea level, situated north of the Himalayas in modern Tibet. None of the four rivers mentioned flows from it, although the Sutlej, a tributary of the Indus, does. Near this lake is a mountain called Kailas, a pilgrimage site sacred both to Hindus and to Tibetan Buddhists. In view of the site’s sacredness, perhaps we may be justified in conjecturing that Manasarowar is indeed Anavatapta. Furthermore, Tibetan legend says that in ancient times the country had greater water resources than it does now and that its lakes were then very large. When they dried up they left smaller lakes dotted around the region. If these legends contain an element of truth, Manasarowar could once have occupied a more extensive area than it does now and might very well have been the common source of the four rivers.
In any case, Anavatapta was a square, each side fiftyyojanas long. According to the Great Commentary, the lake had four “mouths”: in the east, the Ganges flowed from the mouth of a golden elephant; in the south, the Indus flowed from the mouth of a silver cow; in the west, the Oxus (Amu Darya) flowed from the mouth of a lapis lazuli horse; and in the north, the Sita (possibly the modern Yarkand) flowed from the mouth of a crystal lion. What is interesting is that the rivers, on issuing from the lake, immediately made a circuit of the lake (whether clockwise or counterclockwise is not certain) before taking their true
courses.13 The depiction of the rivers as flowing from the mouths of animals probably stems from the same tradition as the spouts in the shape of lions’ heads seen on jugs from the ancient Orient and Greece, on European fountains, and on water outlets in Japanese bathhouses.
Although the courses of the four great rivers are somewhat stylized, they still approximate actual geography. Moreover, the different materials and animals of the four outlets seem to depict the products of the regions in their corresponding directions. For example, in the south were gold and elephants. Gold was considered preeminent among the so-called four precious stones, and its placement in the south no doubt reflected the Indians’ view of the importance of the South Asian continent. It is therefore of interest to see how this view of the world was treated by Buddhists who were not Indian.
Hsiian-tsang (600-664 C.E.), perhaps the best known of the Chinese priests who traveled to India, presents another diagram of the world, one that shows the four rulers of Jambudvipa. In his diagram, the Elephant Lord appears in the south, the Jewel Lord in the west, the Horse Lord in the north, and the Lord of Human Beings in the east. This latter placement raised the status of the east by implying that the eastern land, clearly intended to be China, was where humanity and justice were practiced. The land of the Jewel Lord was the Near East, including Persia, where people valued wealth and possessions, and lacked propriety. The people in the north, in the domain of the Horse Lord, were wild and undisciplined. The land of the south should have been the superior one for a Buddhist, but Hsiian-tsang said that in etiquette and law the east was superior, whereas in religion the south was superior. Incidentally, Hsiian-tsang identified the Slta River as the Yellow River; after disappearing into the desert sands in western China the Sita reappeared further east as the Yellow.
Let us return to Anavatapta for a moment. Why it is called the “lake of no heat or fever” is unknown, although water on the plateau north of the Himalayas should certainly not be hot. For people living in a land of fiery heat, like India, absence of the affliction of heat was a condition of utopia and an indispensable element of a sacred realm. In Kirgiziya (Kirgizstan), just inside the border with China, there is a lake called Issyk-Kul, which means “hot lake.” The area around this lake, which is 1,609 meters above sea level, is said to have a moderate climate, thanks to the water of the lake. From this we can conjecture that a lake of “no heat or fever” might be one with no warming influence on its surroundings, or, to interpret it more positively, a lake that ameliorates heat. Later, it came to be thought that a dragon lord of the same name lived in Anavatapta.
Y. Iwamoto compared Anavatapta and its four rivers with the Garden of Eden and its four rivers. He suggested that Anavatapta, as its name implies, is a mythologization of a desert oasis. The four rivers issuing from it correspond to the four rivers that flowed out of Eden, the Pishon, Gihon, Hiddekel (Tigris), and Phrat (Euphrates). Brahmanical works predating Buddhism tell he same legend of the flood contained in the Old Testament, and thus Iwamoto believes there is very likely a connection between Anavatapta and the Garden of Eden.14
Beside Anavatapta grow tall trees called jambu trees, whose fruit is said to be very sweet; the name of Jambudvipa originates in that of the tree. North of the lake is the mountain Gandha-madana, “mountain of intoxicating fragrance.” According to the Sutra on the Original Cause of the Origin of the World (Ch’i-shih-yin-pen-ching; Dharmagupta’s Chinese translation [ca. 600 C.E.] of the fourth part of the Long Discourses [[[Dirghagama]]]), many kinds of tree grow on the mountain, each emitting its own fragrance. Here live the gandharvas, demigods that serve Indra as musicians. They survive by eating fragrance {gandha}. Under their control are innumerable kimnaras, performers of music and dance. Therefore on this mountain the sound of music is always heard.
Perhaps we could identify this mountain with Kailas (Ti-se in Tibetan). The name of Kailasa appears in the Mahabharata, where it is called the paradise of Siva and as such later became a pilgrimage site for Hindus and later, Tibetans, followers of the Bon religion, as well as Buddhists. It appears that followers of Bon were the first to regard this mountain as sacred and contended with the Buddhists, who came later, concerning its possession.
South of Himavat are three groups of three black mountains. It is tempting to identify these with the Deccan Plateau, but they should more properly be considered the foothills of the Himalayas. Mochizuki’s Buddhist dictionary defines Himavat as follows: “The three groups of black mountains would seem to indicate the ranges in the central part of the Himalayas, which grow taller from south to north. These ranges are the SubHimalaya, the Lower Himalaya, and the Snow Himalaya.”15
It is rather strange to count the Snow Himalaya as one of the groups of black mountains, since “black” signifies a lack of snow. Nevertheless, the black mountains do seem to refer to Himalayan ranges. The photograph in Mochizuki’s dictionary, howing the Himalayas from Darjeeling, shows clearly the contrast between the three groups of black mountains and the snow-covered mountains beyond.
South of Jambudvipa are two islands, on either side of the lower tip of land. They are called Camara and A vara-camara. The island on the east is without a doubt Sri Lanka. West of India’s southern tip are the Laccadives and the Maldives, but they are far smaller than Sri Lanka. The Indians, though, demanded symmetry and conformity, even to the extent of ignoring reality. By the same token, if there were two islands under Jambudvipa, there had to be two islands under the other land masses as well. On either side of Purvavideha are Deha and Videha, Uttarakuru has its Kuru and Kaurava, and flanking Aparagodaniya are Satha and Uttara-mantrin.
The Indians maintained this unreal view of the world even into the present millennium. In Greece, the geographer Ptolemy (Claudius Ptolemaeus, fl. 127-51 C.E.) knew that the world was round and made a world map employing lines of latitude and longitude. But in India, the fifth-century Abhidharmakosa’^ cosmology was ethnocentric: “our” world, Jambudvipa, was shaped like India. Central to any Indian worldview were the commanding, everpresent Himalayas. In Jambudvipa these became the Himavat, the Mountains of Snow, as well as Mount Sumeru itself, on top of the golden earth layer.
The ancient Indians placed the four landmasses to the north, south, east, and west, and thought that their positions were unalterable for as long as the present kalpa lasted (a kalpa is an incalculably long period of time). Our knowledge of continental drift, however, tells us that this is not possible. We know, through examining the directional flow of terrestrial magnetism and the distribution of geological forms, which allows us theoretically to fit continents together, that the Indian subcontinent was once located near the South Pole, connected with Antarctica, Africa, and Australia.
The triangular Indian subcontinent split off from Antarctica ages ago and moved at a snail’s pace until it hit against the floor of the Himalayas on the Asian continent. The impact pushed up the edge of Asia, forming the Himalayas. For some time there remained a gap between the two continents, into which sea water flowed. Over millions of years, sand from the Himalayas filled this gap, forming a layer of sand that at Varanasi is six thousand meters deep. Water flowing down from the mountains formed a river, as indicated in figure 12. The upper Tourse of the river formed the present Brahmaputra, its middle course, the Ganges (flowing in a direction opposite to its present course), and its lower course, the Indus. At some point a great subsidence occurred in the area of Bengal. The river then flowed from that area into the sea and became divided into two rivers, the present Brahmaputra and the Ganges, which changed direction and gathered its waters from a different source. As a result of the Ganges’ shift in direction, the Indus became a separate river. Of course the ancient Indians knew nothing of all this (as we also knew nothing until recently), for the subcontinent had changed position millions of years before human beings appeared, and the sinking of the Bengal area belongs to prehistory.
Sun and moon. The sun and the moon are components of any cosmology.16 Imagine that a large ring of wind (like an inner tube) extends around Mount Sumeru at a height midway between mountaintop and sea level. This wind ring floats high in the air over the four landmasses, supporting and carrying the sun, moon, and stars. The sun is fifty-one yojanas in diameter and the moon, fifty, which makes them about the same size as Lake Anavatapta, north of the Himavat. To judge by the one-yojana difference, Indian Buddhists understood the apparent difference in size between the two bodies to be real. The stars are of varying sizes, the smallest being one krosa in diameter (less than a kilometer). The sun and moon do not themselves float in the ring of wind, but are contained within vehicles or receptacles called vimana, “heavenly palace.” The underside of the vimana forms a circle of fire-pearl (ruby) to make the sun, and a circle of water-pearl to make the moon. Thus the sun shines brightly and is hot, whereas the moon gleams coldly. (The ancient Indians do not seem to have considered that the moon reflects the light of the sun.)17
One sun and one moon circle above the four landmasses. When the sun is over Jambudvipa in the south, it is sunset in the eastern Purvavideha, sunrise in the western Aparagodaniya, and night in the northern Uttarakuru. Why do the lengths of days and nights change in the course of a year? According to the ancient Indians, the reason is that the sun moves continuously between north and south over Jambudvipa. The Abhi-dharmakosa says, “When the sun moves to the southern part of Jambudvipa [daksinayana], the nights grow longer, and when it moves north [[[uttarayana]]], the days grow longer.”18 This analysis is faulty. It is true that the sun continuously moves between north and south. This movement, however, does not explain the changes in the lengths of day and night; for this, knowledge of the earth’s roundness is indispensable. Jambudvipa, however, is on a plane surface.
There is also a problem with the sun’s northward movement over Jambudvipa. The Tropic of Cancer runs through the middle of India (see figure 13). A person living south of the Tropic, say in Hyderabad, would be able to confirm that the sun did move to the north. A sharp-eyed observer living in Delhi, north of the Tropic, however, would be sure to realize that the sun certainly did not pass over his head, that it was not true that “the sun moves to the north of Jambudvipa.” Megasthenes (ca. 3d century B.C.E.), the Greek (Seleucid) ambassador to the Mauryan court at Pataliputra in the Ganges plain, was one such careful observer. He recorded that in certain places in India, shadows at certain times fell to the south, a strange phenomenon to a Greek who had lived only north of the Tropic of Cancer.
What causes the waxing and waning of the moon? “When the house of the moon moves in the vicinity of the house of the sun, then the light of the sun falls on the house of the moon. Conse-quendy, the shadow falls on the opposite side, and the disk appears incomplete.”19 This seems to be a scientific explanation. The moon moves on a circular orbit (the wind ring), as does the sun. If the sun approaches the moon, the shadowed side of the moon should also move. But this is not a sufficient explanation, and the Abhidharmakosa therefore mentions the “manner of revolution’Xt'aAa^oga).
