Ages of the World
AGES OF THE WORLD
AGES OF THE WORLD . The notion that the world or the cosmos, as a living thing, undergoes stages of development similar to those of a human individual is more than a poetic conceit; it is a ubiquitous belief, one that is frequently displayed in linguistic phenomena. For example, lying behind the English word world is an old Germanic compound, *wer-aldh, meaning "the life, or age, of man"; in Indo-European languages, the terms for "life" or "world" and terms designating temporal periods often shade off into each other, as in the Greek aion or the Latin saeculum.
Systems of Binary Periodization
The simplest form of world-periodization is a binary one: before and after, then and now, now and then. The distinction before and after is most frequently expressed in historicized form but often carries with it religious evaluation. Thus, while there are commemorative base years in some chronological systems, such as 4 Ahau 8 Cumkú (3133 bce) among the Maya, 1 Flint (1168 bce) among the Aztec, or the Saka era (78 ce) in India, most such systems are built around events in the lives of founders. The most familiar of these systems is the division of all human history into bc (before Christ) and ad (anno Domini, "in the year of our Lord," i.e., after Christ), a distinction created by the Christian monk Dionysius Exiguus in the first half of the sixth century. Dionysius established the beginning of the Christian era (or the Era of the Incarnation) as 1 January 754 auc (anno urbis conditae, "from the foundation of the city [of Rome]"). The system of dating by ad did not come into wide usage until the eleventh century; the negative chronology of bc gained currency only after the publication in 1681 of Jacques-Bénigne Bossuet's Universal History. However, Dionysius's system ultimately became so widely accepted that it formed the basis of a new system, created in the last decades of the twentieth century, that distinguished between "the common era" (ce) and "before the common era" (bce). (The ce–bce system was soon increasingly favored by English-language scholars and is, in fact, the system employed by this encyclopedia.)
Periodizations similar to the Christian system are found in other religious traditions: the Muslim system of dating events ah (anno Hegirae, "in the year of the Hijrah"), attributed to the second caliph, ʿUmar I (634–644); the Buddhist era, in use in Ceylon and Southeast Asia, which begins with the Buddha's attaining Nirvāṇa in 544 bce; the Jain era, commencing with the death of Jina in 528 bce; and the Kollam era, restricted to the Malabar Coast, associated with Parasurama, an avatāra of Viṣṇu.
The other modes of binary periodization—then and now, now and then —while sometimes found in historicized form (such as the distinction between antediluvian and postdiluvian in Sumero-Akkadian literature) are, more usually, connected to explicit mythical themes, especially those concerned with anthropogony and eschatology. They presuppose that a sharp cleavage may be described as existing between the present state of things and an anterior or posterior state. The contrast between then and now finds its most common expression as that between an ancestral time in the mythical past and the present time of human beings. This contrast may play a dominant role in an entire religious system (as does the notion of the "Dreaming" among the Australian Aborigines), or it may serve as a motif in myths of paradise, of a Golden Age, of the origin of death, of the relocation of a high god, of a deluge, or of a fall. The distinction between now and then occurs widely in apocalyptic and millenarian traditions as in the distinction between this age and the age to come, or in mythologies concerning the end of the world.
As the above suggests, the category "ages of the world" is a somewhat fluid one. At times its primary focus is on the entire universe, at times it is limited to the earth; at times it includes the gods, humans, and all living beings, at times it is centered on man, or on stages of human history. In some traditions all of these aspects are interwoven into a cosmic drama; in other traditions only one or another of these aspects will be found.
Systems of Serial Periodization
In the usual understanding of ages of the world, more than a simple binary periodization is present; there is a system of serial periodization. Three forms predominate: a tradition of world-periods, a tradition of myths of recurrence, and a system of cosmic periods.
The simplest form of serial periodization marks out a succession of periods from creation to final destruction, from a beginning to an end.
It is exceedingly difficult to order the Iranian traditions concerning successive world-periods with any certainty due to the fact that the most elaborate mythic schema are found only in late Pahlavi books redacted no earlier than the ninth century ce. This not simply an internal problem; it affects matters of comparison as well, inasmuch as the Iranian traditions have been held by many scholars to have been influential on Greco-Roman, Israelitic, and Christian traditions of the ages of the world that predate the Pahlavi texts. Nevertheless, elements of the fully elaborated, later traditions can be found in early texts. The myth of the Golden Age of the primordial king, Yima, is a pre-Zoroastrian, Indo-Iranian tradition; the associated notion of a worldwide, catastrophic winter that will destroy terrestrial life is an archaic Indo-European motif. The important title for savior, saoshyant, applied in the first instance to Zarathushtra (Zoroaster), and the notion that the present age will be transformed by the prophet immediately into one that is "excellent" with yet a future age of re-creation and transformation, occur in the earliest Zoroastrian literary strata. What is more important, from Greek reports of Iranian tradition as early as the fourth century bce, one learns of a three-thousand-year period when one god will rule over another; a three-thousand-year period when the two gods will struggle; and a third period, of unspecified length, which will be a golden age. Hades (i.e., Ahriman) will lose power, there will be universal happiness and no need for food, and the god (Ōhrmazd) who achieved these things will be at "rest" (Theopompus, quoted in Plutarch, Isis and Osiris 47). Armenian Christian sources, such as Eznik of Kolb (fifth century), provide the basic elements of the Zurvanist dualistic myth, according to which prior to creation the two rival deities, Ōhrmazd and Ahriman, are each assigned nine thousand years of kingship by their father, Zurwan. Finally, there is the elaborate apocalyptic portrait of the signs of the end fully developed in the Iranian Oracle of Hystaspes (first century bce), well known from its citation in Greek and Latin Christian sources from the second and third centuries.
The Sasanid period (226–652 ce) was one of intense theological controversy between rival cosmologies, out of which emerged the system of dividing the ages of the world into four trimillennia as elaborated in the Pahlavi books. The system received its classic formulation in the Bundahishn (Book of Primordial Creation), itself a composite work containing both elements of orthodox Mazdean speculation and Zurvanist myth. In the first trimillennium, Ōhrmazd and Ahriman coexist in Infinite Time, the former in an upper realm of light, the latter in a lower realm of darkness. After becoming aware of each other and their predestined struggle, they each fashion weapons. At the close of the first trimillennium, Ahriman crosses the Void and attacks Ōhrmazd. Ōhrmazd offers peace and is rejected. Then, knowing that he is destined to win the struggle, Ohrmazd proposes a limit to their contest—a period of nine thousand years. After Ahriman accepts, Ōhrmazd begins a new stage of the battle by reciting the central Zoroastrian prayer, the Ahuna Vairya. Thereupon Ahriman falls back into darkness, where he remains for three thousand years.
During this period of Ahriman's relative impotence, Ōhrmazd brings creation into being. Creation occurrs at two complimentary levels as a series of spiritual and material creations, the latter including Gav-aēvō-dāta (the primordial ox) and Gayō-maretan (primordial man). Ahriman, in his realm, generates his own creations and, at the end of the second trimillennium, invades Ōhrmazd's world. He corrupts it and kills Gayō-maretan and Gav-aēvō-dāta, out of whose bodies humans, other living things, and metals are generated.
The third trimillennium is Ahriman's triumph, but this turns out to be a trap. Ahriman is caught in the material world. The final trimillennium is devoted to the salvation of the world, beginning with the birth of Zarathushtra. Each of the three millenniums will be marked by a savior (a descendent of Zarathushtra) until the final millennium of Saoshyant, when there will be a final judgment, the granting of immortality, and a new world. This basic myth was adapted to a variety of systems of Iranian religious thought; a further permutation occurs in the myth of the Three Epochs in Manichaeism.
There appears to be no indigenous Israelitic tradition of the ages of the world. The historicized sequence in the Book of Daniel (second or third century bce), so influential on later Jewish and Christian periodizations, of four world-empires followed by a divine kingdom and symbolized by metals or beasts (Dn. 2:37–45, 7:2–27) is an adaptation of Iranian anti-Hellenistic propaganda. Based, perhaps, on the sabbath-week, there is a noticeable predilection for multiples of seven. Already in Daniel 9, history from the Babylonian exile to the End is divided into seventy weeks of years (i.e., seventy heptads). Similar periodizations recur in a variety of early Jewish works (second century bce–second century ce). There are schemas that divide the world into seven ages of a thousand years each (Testament of Abraham 19) or six ages of a thousand years plus a millennium of rest (2 Enoch 33:1–2). The "Apocalypse of Weeks" divides history into ten weeks of unequal length: seven weeks are past history, three are the age to come (1 Enoch 93:1–10, 91:12–17). The complex calculation of jubilees (seven times seven) is employed to periodize history from creation to new creation in the Book of Jubilees and the Assumption of Moses. The duration of "this world" in contradistinction to the "world to come" is frequently given as seven thousand years, less frequently six thousand, with a division into three ages: the Age of Confusion, the Age of the Torah, and the Age of the Messiah (B. T., San. 97b, ʿA. Z. 9b). The other numerological system, apparently borrowed from the Iranian, focused on twelve periods (2 Bar. 56; T. Ab. 7b; Apocalypse of Abraham 20, 28), with the most tantalizing schema presented in the brief report in 2 Esdras 14.11 (4 Esdras in the Vulgate) that the age of the world is divided into twelve parts, nine parts; and half of the tenth have already passed, two parts and the second half of the tenth remain. However, the basic distinction in the Jewish rabbinic traditions remains persistently dualistic: there are two ages of the world, "this age" (ha-ʿolam hazeh ) and the "age to come" (ha-ʿolam ha-baʾ ).
The emerging Christian traditions of the ages of the world must be seen first in relation to the Jewish. The primitive Christian writings of the first century focused on the central duality of "this age" and the "age to come" (Mt. 12:32, Eph. 1:21), being convinced that "the end of the ages has come" (1 Cor. 10.11). In the second and third centuries, building on contemporary exegesis of Psalms 90:4 (i.e., that a day for the deity equals a thousand years) and Asian Christian traditions of a thousand-year earthly reign of Christ (the millennium), which will be a Golden Age (Rv. 20:2–7; Papias, in Eusebius, Church History 3.39.1–2; Justin, Dialogue 81.3–4; Lactantius, Divine Institutions 7.24), and joined to Jewish speculations on the sabbath-week, the hexameral system was developed. This system postulated that the first six days of creation, understood as a period of six thousand years, represented the history of the world; the seventh day represented the thousand-year reign of Christ or the end of the world; occasionally an eighth day would be added, signifying "the beginning of another world" (Barnabas 15.3–8; Irenaeus, Against Heresies 5.28.3; Methodius, Banquet 9; Victorinus of Pettau, On the Creation of the World 6; Hippolytus, Commentary on Daniel 4.23). In such a periodization, the period of the Incarnation would either be placed in the middle of the sixth millennium (that is, 5,500 years since creation, as in Theophilus, To Autolycus 3.28) or at its close (the year 6000, as in Pseudo-Cyprian, Sinai and Zion 6). The sabbath-week system at times interacted with a fourfold system of periodization loosely based on Paul in Galatians 3.15–26: a period before the law; the period of the law; the period of the prophets; and, equivalent to the sabbath, the period of grace or freedom.
The most influential Christian ages of the world system was that briefly sketched out in the penultimate paragraph of Augustine's City of God (22.30) in the first quarter of the fifth century. The first age was from Adam to the Flood, the second from the Flood to Abraham, the third from Abraham to David, the fourth from David to the Babylonian exile, the fifth from the exile to Christ, the sixth age was the present Christian era, the seventh would mark the millennium, followed by an eighth "eternal day" of repose. Although Augustine noted temporal symmetry within the first five ages, he freed the schema from its rigid chronological limitation to a total of five or six thousand years. This flexibility allowed Augustine's system to be the base of most medieval Christian theories and to be influential through the Renaissance (see Coluccio Salutati's letter to Zonari of 5 May 1379).
Over time, modifications of the Augustinian schema were introduced. The eighth age was largely ignored. Some authors, such as Philipp van Haveng in the twelfth century, introduced the notion of an alternation of good and evil ages. The most significant modification was the work of the Calabrian mystic Joachim of Fiore (1132–1202). Joachim's work was a dazzling set of interrelated schemata built around twos, threes, sixes, sevens, and twelves. Alongside the traditional notion of "age" (aetas ), Joachim introduced the terminology of "stage" (status ) so that each period was seen as progressive toward a historical fulfillment and as "incubating" its successor. The first five ages, as in Augustine, extended from Adam to Christ, the sixth age was the era of the church; the seventh, the time of consummation. Further schemata were superimposed on this traditional outline. Within the first four ages, the period from Abraham to the prophets was the first stage, that of the Father, with a period of germination from Adam to Jacob and of fruition from Jacob to the prophets. The second stage, that of the Son, extended from the prophets to the present (c. 1260), with a period of germination from the prophets to Christ and of fruition from Christ to Benedict of Nursia. This second portion (which corresponds to the sixth age) was divided into six smaller periods (etatulae ) with Joachim's times at the end of the fifth period. Yet ahead was the third stage of the Holy Spirit where, following the defeat of the Antichrist at the end of the second stage, a "new people of God" would be brought into being. It will be a Golden Age without labor, heaven will descend to earth, and life will be lived in beatific ecstasy.
Such mythic schemata persist in more secular, Western historical periodizations, but they have interacted as well with non-Christian mythologies in a variety of recent nativist movements, such as the Kugu Sorta ("big candle") movement among the Mari (Cheremis) in Russia. According to this tradition, human history began with a Golden Age and will return to one at the end of time. In between are seventeen historical ages, the present being the ninth. Beginning with the tenth age, the earth will become uninhabitable except by members of the sect.
Myths of recurrence
In a second form of serial periodization, the same series is repeated through multiple cycles of creation or activity.
It would appear that, based on their careful astronomical observations of periodicity, late Babylonian cosmologists (e.g., Berossos, third century bce) developed the notion of a repetitive cosmic "great year" divided into two seasons: summer, when all the planets were in conjunction with Cancer, would result in world-conflagration; winter, when the planets were in conjunction with Capricorn, would produce a universal flood (Seneca, Naturales quaestiones 2.29.1; the schema is attributed to Aristotle in Censorinus, De die natali 18.11). As brought over into Greco-Roman thought, the duration of the "great year" was fixed at 12,954 ordinary years (Cicero in the Hortensius according to Tacitus, Dialogus de Oratoribus 16.7). This period was later identified by Christian authors as the life span of the phoenix (Solinus, Collectanea rerum Memorabilium 33.13). Berossos himself appears to have used a far larger time scale. He fixes the reign of the ten antediluvian kings as lasting 432,000 years (a number that is the same as the Indic kaliyuga, which was probably influenced by Babylonian speculation).
Most likely influenced by the Babylonian "great year," there was a lively Greek and Roman philosophical debate over recurrence, conjoined at times to the topic of the eternity of the world or the plurality of worlds, at other times to the transformation of the Hesiod myth of the five races of men into the later myth of the five or four ages of humanity. Although foreshadowings of this debate can be found in earlier Greek writers, it was most fully developed by the Stoics, many of whom came from the hellenized Near East. This world is but the present member of a series of identical worlds. At a particular planetary conjunction, the world will be destroyed by fire (ekpyrōsis ), and, following another conjunction, will be restored out of fire "precisely as before." The elements of the cosmos will be in their same place, each individual life will recur with exactly the same experiences. There will be no novelty; "everything is repeated down to the minutest detail," not just once, but over and over again without end (Nemesius, On the Nature of Man 38).
In the Vǫluspá and in Snorri's Gylfaginning, a myth of both the creation and eventual destruction of the world is presented what appears to be an instance of a common Indo-European pattern. A series of worlds came into being around the great world-tree, Yggdrasill. Following a series of creative acts, the gods and then humans came into existence. After a long period, there will come Ragnarǫk, the destruction of the gods and man, preceded by Fimbulvetr, the great worldwide winter (compare the Iranian myth of Yima). The Great Snake will emerge from the ocean and flood the world; demons attack Ásgarðr, the home of the gods, and the gods and demons meet in cosmic battle in which each side slays the other. Finally, the only survivor, the giant Surtr, sets off the cosmic fire that will destroy the world. There are disparate hints that this is not the final end. The world will be restored, the sons of the dead gods will return, Baldr will reemerge, the two surviving human beings (Líf and LífÞrasir, "life" and "life-holding"), having been sheltered by the world tree, will repopulate the earth, and the cycle continue. (Voluspá 31–58; Snorri, Gylfaginning 51–53; Vafruðnismál 44–45).
Cosmic periods of creation
The most complex form of serial periodization features a mythology containing a series of cosmic ages, related to each other, although separated from one another by catastrophes, so that each successive creation is both a new act and, in some sense, a recapitulation of its predecessors.
One of the most complex systems detailing the endless repetition of cosmic ages of the world was developed in India. Although elements occur in earlier texts, the systematic elaboration appears to be a development largely of the epic and Puranic literature between the fifth and third centuries bce. While largely indigenous in its full expression, aspects of the system reflect the considerable interaction between Near Eastern, Hellenistic, Iranian, and Indian traditions of that time as well as more archaic Indo-European motifs.
The fundamental schema is built around a complete cycle of cosmic existence (mahāyuga ), divided into four ages (yuga s) of unequal length and valence, each preceded and followed by a period of transition, a "dawn" or "dusk" of proportionate duration. In its most abstract form, the four ages are correlated to throws of dice: the kṛtayuga (4), the tretāyuga (3), the dvāparayuga (2), and the kaliyuga (1). This system yields various proportional measurements for the duration of each age in different traditions: 4000/3000/2000/1000 or 4800/3600/2400/1200 or 1,728,000/1,296,000/764,000/432,000 years, yielding equivalent measurements for the length of a mahāyuga : 10,000 or 12,000 or 4,320,000 years. In the fully elaborated system, even more extended numbers are employed. A thousand mahāyuga s equal one kalpa, which corresponds to either a day or a night in the life of Brahmā (his total life is 311,040 billion human years). Within each kalpa are fourteen secondary cycles (manvantara s), each preceded by the destruction and re-creation of the world and a new manifestation of Manu, the progenitor of the human race. (For major versions of the yuga myth, see Bhāgavata Purāṇa 3.11.6–37; Brahmāṇḍa Purāṇa 1.7.19–63 and 1.29.4–40; Viṣṇu Purāṇa 1.3.1–25.)
The fully developed myth of the four yuga s is essentially a cosmogony described in temporal language, yet it contains within it several strands of tradition well-integrated in some versions but capable of appearing independently in other texts. One such strand is a numerical tradition that elaborates the basic schema of four proportional periods into vast cosmic numbers. This numerical schema is correlated with a tradition of the decline of dharma. Thus the kṛtayuga is also known as the satyayuga ("age of truth") and is characterized by elements drawn from the well-developed and independent Indic mythology of a Golden Age. The tretāyuga is characterized by a diminution of virtue and by the introduction of death and labor into the human sphere, that is to say, by an end to the Golden Age. The dvāparayuga marks the transition to the degenerative half of the cycle: evil increases, and the human life span decreases. The kaliyuga, which is the present age, dated by some as having begun in 3102 bce (the traditional date of the war recounted in the Mahābhārata ), is a period of discord and disintegration wherein evil triumphs. Through this correlation, the cosmogonic structure of the yuga s has been transformed into an anthropology. The yuga myth is further intertwined with the mythology of Brahmā and Viṣṇu, especially their roles in the rhythmic expansion and contraction of the cosmos. This element is especially prominent in accounts of the mahāpralaya, the "great dissolution" (Matsya Purāṇa 167.13–25). Finally, there is the royal mythology of the Manus and the avatāra s of Visnu, expressed in the manvantara cycle.
With important modifications and different soteriological implications, the Indic cosmic ages were adapted by both Buddhism and Jainism. The Indic system was influential as well on Neo-Confucian speculations on the ages of the world.
Among the northern Maya, there is considerable evidence for both the conception of time (kin ) without beginning or end that allows vast chronological computations extending back four hundred million years, a duration that encompasses all past and future world cycles, and the mythic notion of a number of previous worlds, each terminated by a universal flood.
In the Aztec traditions, as exemplified by the more than twenty versions of the myth of the suns, the Leyenda de los Soles, and as carved on the so-called Calendar Stone, a more complex picture is presented. Superimposed on an archaic myth that, like the Maya, depicted a continuous series of cosmic creations and destructions, is a myth of five suns, each marking an age of the world as part of a cosmogonic drama involving the struggles for supremacy among the Tezcatlipocas, the sons of the androgynous supreme deity, Ometeotl. Each one would create a world only to have it destroyed by another. Four such primeval worlds are identified, each named after the mode of their destruction: the world of the first sun, 4 Jaguar, which lasted 676 years until its inhabitants were devoured by jaguars; the second sun, 4 Wind, which lasted 364 years, until winds blew away its inhabitants; the third sun, 4 Rain of Fire, which lasted 312 years, until its people were destroyed by a heavenly fire; and the fourth sun, 4 Water, which lasted 676 years and ended in a universal deluge. The fifth sun, 4 Movement, is the world that the Aztec inhabit and represents a revolution in the cycle of creation and destruction. Rather than the peripheral symbols of the four cardinal directions, with which the previous worlds are identified, the fifth sun is the world of the center, guaranteed by an agreement between the rival deities and by divine acts of self-sacrifice.
For a general orientation from a broad comparative perspective, see Mircea Eliade's Cosmos and History: The Myth of the Eternal Return (New York, 1954), esp. chap. 3. The articles under the heading "Ages of the World" in the Encyclopaedia of Religion and Ethics, edited by James Hastings, vol. 1 (Edinburgh, 1908) are badly dated in their interpretation (the article on Babylonian systems should be ignored), but they do provide a useful anthology of texts in translation from a variety of traditions. Gary W. Trompf's The Idea of Historical Recurrence in Western Thought: From Antiquity to the Reformation (Berkeley, Calif., 1979), albeit devoted to a parallel theme, is the best interpretative history of world-periodization in Western thought.
On Iranian traditions, R. C. Zaehner's book The Teachings of the Magi (London, 1956) provides a brief exposition and translated sections from the late Pahlavi books. Geo Widengren's Mani and Manichaeism (New York, 1965), pp. 43–73, emphasizes the Iranian elements in the Manichaean schema. Joseph Ward Swain's "The Theory of the Four Monarchies," Classical Philology 35 (January 1940): 1–21, remains the classic statement on the relationship of Iranian to Israelitic schema; D. S. Russell's The Method and Message of Jewish Apocalyptic, 200 B.C.–A.D. 100 (Philadelphia, 1964), pp.224–229, gives an adequate summary of the early Jewish materials.
Jean Daniélou's definitive article "La typologie millénariste de la semaine dans le christianisme primitif," Vigiliae Christianae 2 (1948): 1–16, is summarized in his The Theology of Jewish Christianity, edited and translated by John A. Baker (London, 1964), pp. 377–404; Auguste Luneau's L'histoire du salut chez les Pères de l'Église: La doctrine des âges du monde (Paris, 1964) is extremely detailed on the patristic materials. Marjorie E. Reeves's Joachim of Fiore and the Prophetic Future (London, 1976), pp. 1–28, provides the best brief exposition of Joachim's system.
Thomas A. Sebeok and Francis J. Ingemann's Studies in Cheremis: The Supernatural (New York, 1956), pp. 320–337, gives the basic information about the Kugu Sorta. On the Babylonian great year, the essential study is B. L. van der Waerden's "Das Grosse Jahr und die ewige Wiederkehr," Hermes 80 (1952): 129–155. The Greek materials have been well surveyed by Charles Mugler in Deux thèmes de la cosmologie grecque: Devenir cyclique et pluralité des mondes (Paris, 1953), although some of his interpretations are fanciful. The entire notion of recurrence is brilliantly treated in Trompf's The Idea of Historical Recurrence in Western Thought, cited above.
The classic study of the Scandinavian myth remains Axel Olrik's Ragnarök: Die Sagen vom Weltuntergang (Berlin, 1922), but see Georges Dumézil's Gods of the Ancient Northmen, edited by Einar Haugen (Berkeley, Calif., 1973), chap. 3, for its setting within archaic Indo-European mythology. A major text in translation, with valuable footnotes, illustrating the Indic system of yuga s is provided by H. H. Wilson in The Viṣṇu Purāṇa (London, 1840), vol. 1, pp. 44–67, now available in a second edition (Calcutta, 1961). C. D. Church gives a rich bibliography in "The Myth of the Four Yugas in the Sanskrit Purāṇas," Purāṇa 16 (1974): 5–25. The Indic, Buddhist, and Jain traditions are interpreted in Eliade's "Time and Eternity in Indian Thought," in Papers from the Eranos Yearbooks, edited by Joseph Campbell, vol. 3, Man and Time (New York, 1957), pp. 173–200. For a translation and commentary on the Aztec myth of the suns, see Miguel León-Portilla's Aztec Thought and Culture: A Study of the Ancient Nahuatl Mind (Norman, Okla., 1963), pp. 35–48.
Jonathan Z. Smith (1987)