Tribes, Traditions and Numbers: The American Model in Southern African Iron Age Ceramic Studies

South African Archaeological Society

Tribes, Traditions and Numbers: The American Model in Southern African Iron Age CeramicStudiesAuthor(s): Martin HallSource: The South African Archaeological Bulletin, Vol. 38, No. 138 (Dec., 1983), pp. 51-57Published by: South African Archaeological SocietyStable URL: http://www.jstor.org/stable/3888636 .

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The South African Archaeological Bulletin 51

TRIBES, TRADITIONS AND NUMBERS: THE AMERICAN MODEL IN SOUTHERN AFRICAN IRON AGE CERAMIC STUDIES*

MARTIN HALL South African Museum P. 0. Box 61, Cape Town, 8O00

ABSTRACT

This paper is a critical evaluation of T. N. Huffman's contribution to Iron Age research in southern Africa. Huffman's work with ceramic assemblages forms a basis for most syntheses of the later prehistory of the subcontinent, yet he has incorporated a number of implicit, untested assumptions about the nature of Iron Age society. It would appear that these assumptions are modifications of the source theory for Huffman's approach, and that they represent adaptation to general, southern African beliefs about the nature of tribal life. When Iron Age studies are examined in their historical perspective, it appears that ideas of tribalism have affected the interpretations of others as well. I suggest that such subjectivity is reinforced when analysis is conducted in the belief that classifications are inherent in data, rather than devices dependent on research problems. * Manuscript received January 1983, revised June 1983

One of the more prolific and influential interpreters of the southern African Iron Age in recent years has been T. N. Huffmnan. His research is central in any attempt to understand, from existing sources, the nature of the Iron Age south of the Zambezi. In addition to this empirical contribution, Huffman has also introduced Iron Age studies to a methodology that differs significantly both from earlier approaches and from the concepts employed by many contemporary research workers.

Precisely because Huffman's work has been so extensive and important, his interpretations should be scrutinized critically before they become accepted lore. Without such an evaluation, under- standing the Iron Age may come to rest on argument by authority rather than on tested and well-weathered hypotheses. Such assessment is attempted in this paper, which is an examination of Huff- man's approach to Iron Age ceramic analysis.

Background: the British Model Although the term 'Iron Age' was adopted formally only some

thirty years ago (Summers 1950; Mason 1952), modem studies of southern African farming communities can be traced back to 1931 when Gertrude Caton-Thompson published the results of her work at Great Zimbabwe. Reacting to the romantic claims and loose methodology of Hall and Neal, and conscious that MacIver had failed to establish firm dating evidence, Caton-Thompson was cautious in her synthesis, building a ceramic sequence for Great Zimbabwe and its immediate area from the results of excavation and avoiding the temptation of general extrapolation. In similar style, Schofield (1935, 1937) built regional sequences in those areas where he worked and then brought together his information in a general overview that was to serve as a framework for Iron Age research in southern Africa for many years (Schofield 1948). In 1950, Caton-Thompson's system for the Great Zimbabwe area was superseded by Summers's ceramic classification for Southern Rhodesia, built on the model of the British Iron Age, and this scheme was supplemented by Robinson's work in the south-west of the country (1959, 1963, 1966) and by Summers's own continu- ing investigations (Summers 1967).

In this early phase of research, concepts were drawn principally from British prehistoric studies. Thus Summers was influenced strongly by Gordon Childe's idea of culture, which allowed sets of assemblages to be seen as the material remains of a past society (Summers pers.comm.). In keeping with the functionalist ideas then dominant in British anthropology, these archaeological cul-

ture-societies were seen as unchanging units, replaced by similar units through the process of migration and invasion.

In southern Africa, this British culture model was reinforced by ethnography. Earlier writers had emphasized the barbarism of in- digenous farming communities, assigning tribes to positions in an evolutionary hierarchy according to nineteenth century concepts of social evolution. Such societies were believed to be largely incapable of change unless stimulus came from another group at a higher level. Thus Soga (1930:8) wrote that ". . . the Negroes are of themselves incapable of civilization and intellectual advancement, unless their blood has had an infusion from that of more highly developed races." Similar overviews were offered by writers such as Stow (1905) and Theal (1907).

With the influence of functionalism on African studies came the rejection of such sweeping prejudices, but also a suspicion of any- thing other than the close and detailed account devoid of diach- ronic speculation. Indeed, functionalist anthropology was not equipped to deal with change through time. The result was a set of separate cameos in the 'ethnographic present' (for example, Stayt 1931; Hunter 1936; Krige & Krige 1943; Kuper 1947). Un- derstandably, the ceramic units defined and mapped in the earlier syntheses of southern African prehistory were seen as tribes and 'peoples' in this same static way (Hall 1981). Thus Robinson (1963), for example, was able to use 'culture', 'people' and ceramic class synonymously, and to link these archaeological constructs to a linguistic grouping from the ethnography. Similarly, Summers and Robinson interpreted the Great Zimbabwe sequence as a series of set phases separated by migrations, rather than as a his- tory of internal change, as the data equally allowed (Garlake 1973).

The American Approach Although British archaeology had a dominant influence in

southern Africa for many years, there was also an early influence from American prehistory. Between 1949 and 1950, Revil Mason had excavated deposits in rock shelters close to Johannesburg and, in his interpretation of this information, he suggested the application of Wissler's 'culture area' concept (Mason 1952). In later pub- lications, Mason has pursued this idea of culture-area, seeing particular ceramic styles linked to specific geographical areas. Thus Uitkomst pottery was seen as a uniform culture, spanning the gap between the Later Stone Age and contemporary 'Sotho - Tswana people' (Mason 1962). More recently, Mason has stressed cultural continuity in the Magalies Valley, north of Pretoria, with a direct evolutionary relationship between Early, Middle and Late Iron Age, and a design connection between first millennium Early Iron Age ceramics and the pottery of contemporary communities (Ma- son 1981).

Mason's concept of the culture-area is an interesting sub-theme within Iron Age studies, for its interpretative implications are different from those of both British cultural-functionalismr and later American influences. Almost by definition, however, the emphasis on the region in Mason's research has restricted the influence of his ideas to those areas where he has conducted fieldwork. Natu- rally, models that postulate diffusions and migrations beyond the study area will tend to have a concomitant breadth of impact on the general synthesis of prehistory.

One such generalizing approach has also come from American archaeology. In 1966, Robinson published a sequence for his Leopard's Kopje Culture of south-western Zimbabwe. He emphasized that his conclusions were tentative and, indeed, an apparently contradictory radiocarbon determination became available as his

S. Afr. archaeol. Bull. 38: 51-57. 1983



52 The South African Archaeological Bulletin

paper went to press. Robinson's sequence attracted the attention of T. N. Huffman, then a graduate student in America, who first carried out a seriation study based on the published illustrations of ceramics, and then a different interpretation, incorporating the results of additional fieldwork (Huffman 1968, 1974a). In addition to offering a revision of the Leopard's Kopje Culture, however, Huffman also departed from the principles of the British model, dominant in southern African Iron Age studies since Gertrude Ca- ton-Thompson's seminal work at Great Zimbabwe.

Huffman has been reticent about the theoretical and method- ological base of his approach, referring to the "codified body of theory that exists within archaeology concerning classification and the construction of sequences" (1979a:235) without specifying where such theory resides. But the methodology of his analyses suggests that Huffman's strongest connections are with what Wil- ley and Sabloff (1974) have called the 'classificatory - historical' school of American archaeology. A basis for this approach has been set out by Dunnell (1971) in his examination of 'archaeological systematics'. Dunnell appears to reject the logical positivism of the 'new archaeology' for a form of empiricism, distinguishing between a 'phenomenological realm' in which information exists, and an 'ideational realm' of analytical concepts. This same perception of reality appears to run beneath Huffman's work, accounting for his distinction between 'descriptive domains' and 'explanatory domains' (Huffman 1981a) as well as for his feeling that 'real' classificatory systems exist. Such systems, Huffman feels, will have been found when the archaeologist succeeds in matching his classifications with those employed by prehistoric communities (Huff- man 1968), and he makes use of a number of descriptive and analytical devices to discover them. These will be evaluated later in this paper.

Although Huffman (1970) has complained of the lack of precise terminology in Iron Age studies, his own work is a confusing land- scape of synonyms and undefined concepts, and some investigation is needed before analysis of the approach itself is possible. As with the British approach, the central focus of Huffman's work has been ceramics, within which he sees four 'dimensions' of function, shape, size and decoration, although the first of these, rarely apparent in archaeological data, may be disregarded without too much risk to the analysis (Huffman 1972a). Within each dimen- sion are 'attributes', also referred to as 'modes' and the basis of the original 'modal seriation' carried out on the Leopard's Kopje material (Huffman 1968). Modes are basic to the American classificatory - historical method and were employed by Rouse in his seminal examination of the prehistory of Haiti, and by Dunnell in his discourse on systematics more than three decades later (Rouse 1939; Dunnell 1971). In Huffman's work, the concept of the mode would seem to encompass 'core feature' and 'theme', the latter defined as 'particular motifs in particular positions on particular shapes' and therefore apparently a special case of the mode (Huff- man 1976: 53).

As Huffman does not define his use of the mode concept, it is instructive to go back to Rouse's original formulation. Rouse em- phasised that, in splitting artefacts into their individual parts rather than classifying them, the mode is an analytical concept: "Each mode . . . is an abstraction of a recurring feature from the speci- men ... a cultural pattern, or standard of behaviour, which influenced the artisan's procedure as he made his artifact. It is a community-wide technique design, or other specification to which the artisans conformed. Modes representing techniques might be considered analogous to habits, which the artisans learned to per- form by imitation of other artisans in the community. Modes con- sisting of designs, on the other hand, might be conceived as visual patterns, which guided the artisan as he made the artifacts. Simi- larly, modes which specify certain material qualities in artifacts would be ideas, to which the artisan conformed in making the artifacts" (Rouse 1939:18-19).

If Huffman's terms are visualized as a hierarchy then at the next level, involving more than the individual mode, is the 'type' which, Huffman (1979a:233) tells us, "can be seen as clusters of significant stylistic attributes." It would seem that the type has at least a partial equivalent in the 'core concept' which consists of "the essential ideas that govern the clustering of attributes" (Huff-

man 1978:2). Again, it is helpful to turn to the American literature for clarity

concerning types. Dunnell (1971:157) confirms the relationship between mode and type, defining the latter as a 'class of discrete objects defined by modes', while Rouse has provided an expanded definition on the concept, writing that "each type ... is a standard of artifact appearance towards which the artisan was working in making a given type of artifact. It is analogous to a style, to which the artisan tried to make his completed artifact conform. Like a style, it outlines limits within which the appearance of an artifact can vary. It prescribes the alternative features which an artisan can apply to an artifact and still have it remain in style. In effect, therefore, it is a visual image of the ways in which such an artifact may look when completed" (Rouse 1939:18). Thus types are whole artefacts, although not necessarily any particular whole artefact, while modes are individual elements of design.

The mode and the type are the building blocks for higher levels of abstraction - the 'phase' and the 'tradition'. Here, matters are clearer. For Huffman, the ceramic tradition is "the development of a particular assemblage through time" (1971), the "time depth of a decoration theme" (1974a) and a 'style system' which "com- prises all the possible modal combinations in an assemblage" (1980). The phase is "a specific time segment of a tradition" (Huffman 1971). A linked concept is the 'co-tradition' (Huffman 1970, 1971), defined by Rouse (1957:128) as a series of traditions with a common origin which have descended by 'the process of bifurcation'.

Similar concepts from American methodology have also been applied by T. M. Evers in his examination of the Iron Age of the eastern Transvaal. Thus the use of the term 'tradition' is described as being 'in the American sense' (Evers 1973), while the concept of 'attribute' is used as an apparent equivalent of the mode in the analysis of ceramic shape, decoration layout and motif (Evers 1977a). In his general consideration of ceramics from the eastern Transvaal, Evers (1977a) defines twelve 'classes' of pottery that seem equivalent to Huffman's types, while in a more detailed re- port on the assemblage from the site of Plaston, Evers (1977b) employs Huffman's (1976) analysis of ceramics from the Goko- mere Tunnel site as a model, now using modes (attributes) to define types (classes). Evers's later analysis of the ceramics from the important Lydenburg Heads site is more sophisticated, with classes (types) identified by means of a multidimensional technique. In this case, however, the units for the multi-dimensional analysis are called 'modes' and the resultant types referred to traditions (Evers 1982). This examination of Evers's and Huffman's applications of classificatory-historical methodology allows identification of the point of departure from the earlier, British derived model of Summers, Robinson and their colleagues. The distinction can be conceptualized as a matter of scale and precision. Although the British school employed terms such as 'class' and 'ware', the 'culture' was the primary unit of classification and this was loosely equivalent to 'people' in the ethnographic sense. Archaeological synthesis was a matter of defining and naming boxes within the co-ordinates of space and time (for example, see Summers 1950, 1967). In the American school of Huffman and Evers, the basic unit of analysis has been the type, both smaller and more clearly defined than the culture. Since the type is identified at the level of the individual assemblage, Huffman and Evers have approached the analysis of the southern African Iron Age with a far greater attention to detail than their predecessors.

The Response of Theory to Environment Although Huffman's approach to the southern African Iron

Age can be traced unequivocally to American methodology, the form that his interpretations of the subcontinent's prehistory have taken show interesting modifications. These suggest that, behind the methodology so well established in the New World, Huffman has a different underlying perception of the nature of change in prehistory .

A first departure is in the idea of 'culture'. In outlining his analytical method, Rouse (1939) was cautious of an easy assocation between the ethnographic concept of culture and the archaeological units that resulted from artefactual analysis. Huffman appears




to follow this same line in his major revision of the Leopard's Kopje material, divorcing his examination of the ceramics from evidence for prehistoric lifeways, which is gathered together in a final chapter that deals with the Leopard's Kopje 'culture'. Else- where, however, culture is said to be "synonymous with tradition" but to include "all other aspects of society as well" (Huffmnan 1971). Later, this slight distinction seems to have fallen away, for we are told without qualification that the tradition "is interchange- able with the term archaeological culture" (1974b).

A second area of ambiguity is Huffman's attitude to the concept of time. In the classificatory-historical approach, stress has been laid on continuity. Thus for Rouse (1957:128), the tradition was "a series of phases which have developed out of one another and which therefore form a single cultural continuum, persisting over a relatively long period of time." In addition, "each phase has given rise to the one which followed it, so that they form a genetic line, developing through time." Huffman emphasized this same concept of change in his revision of the Great Zimbabwe sequence. As we have seen, Robinson and Summers saw the sequence as a set of discrete cultural blocks not, it may be suggested, because of the ideas of diffusion and migration in themselves, but because Childe's culture model did not allow any other frame of thought. Huffman's theoretical background enabled him to write of Great Zimbabwe that "the 'one-class one-people' interpretation appears to be based on an a prion assumption that ceramic change must be initiated by outside influences, and that change over time is not a normal process. The converse assumption, that change is normal, is equally plausible" (Huffman 1972a:356).

Elsewhere, however, Huffman's notion of the form that change may take has been circumscribed. Thus in a general statement concerning the nature of the southern African Iron Age, Huffman (1979a:234) concludes that archaeological units have "meaningful spatial and temporal boundaries with relatively few transitional sites because of the pattern produced by discontinuous change. In terms of stylistic types archaeological entities do not continuously grade into one another in space or time. They belong to one particular space or time unit, rather than any other, because they possess only one set of modes out of several mutually exclusive possibilities." Huffman calls this sort of patterning the 'stepped- continuum'. At a more specific level, Huffman (1976: 53) notes that ceramics of the first phase of the Gokomere Tradition reveal a consistent theme, thus supporting "the premise that ceramic in- novation is limited to short intervals between long periods of sta- bility."

It would seem that Huffman has taken this idea of the nature of change from Spaulding's (1960) exploration of the dimensions of archaeology. In discussing the nature of form-time relationships in prehistory, Spaulding suggested that innovations would tend to cluster on the time scale; "The view of cultural dynamics underlying the concept is that a typical mode of cultural change is the achievement of a key invention - a sort of quantum advance - followed quickly by a number of functionally related auxiliary innovations. The short periods of rapid change would be separated by relatively long periods of comparative quiescence, although not of total cultural stagnation, of course" (Spaulding 1960: 453). Spaulding's idea was an 'assertion' in which the term 'artefact' was interpreted in its broadest sense. Huffman, however, has taken the hypothesis of discontinuous change as an axiom, relating it to a particular and restricted area of total artefact variability - ceramic design.

Thus where Rouse and those who followed his approach in the New World have seen change in prehistory as a complex pattern of recombining traits with few clear temporal boundaries, Huff- man has seen the tradition as a set of far more discernible phases, each with much in common with the general notion of a 'culture'. The significance of this departure becomes apparent when Huff- man's work is considered against the background of southern Afri- can ethnography, for his modification of theory has allowed him to integrate his interpretations with ethnolinguistic classifications in the subcontinent.

Although the tenor of American archaeology has been anthro- pological, and although the ultimate aimn of the classificatory-historical school has been to integrate prehistoric data with

information collected in the 'ethnographic present' (Willey & Sab- loff 1974), most theorists have been cautious in identifying units in ceramic analysis with specific social formations. Thus Willey and Phillips (1958:48), for example, expressed their 'extreme trepida- tion' in suggesting that a regional artefactual grouping may be considered the equivalent of 'tribe' or 'society'. In addition, they were not hopeful for the prospects of comprehensive reconstruction, ob- serving that "we seldom experience the satisfaction of feeling that our units are coextensive, either spatially or temporally, with cor- responding social units, even in the simplest and most explicit of archaeological situations." Perhaps sensibly, Dunnell (1971:132) kept the relationship between archaeological systematics and human behaviour extremely general, declaring that "the basis of all prehistory" is the assumption that "attributes which are the pro- ducts of human activities and which recur over a series of artifacts... can be treated as manifestations of ideas held in common by makers and users of those artifacts."

Huffman is prepared to be far more specific, arguing for 'ethnohistorical reconstruction' by using ethnographic observations to explain archaeological patterns 'in the same historical line' (Huffman 1971, 1974b, 1981a). Logically, such an approach could be severe- ly restricted, for if we are to accept the axiom of discontinuous change, then such 'historical lines' are likely to have been some- what short-lived, rendering the prospects for such ethnohistorical reconstruction inauspicious. The only way out of this cul-de-sac is to assume such historical lines to be extremely broad; a position that Huffman does indeed take by adopting Kuper's concept of a 'Southern Bantu' culture area (Kuper 1980; Huffman 1981b). With such wide terms of reference, however, any value of histori- cally linked analogy is greatly diluted, and ethnohistorical reconstruction begins to take on the identity of general ethnographic analogy. It is at this point that the significance of Huffman's use of Spaulding's discontinuous change model becomes clear, for it is far more appropriate to equate static ethnographic models with static segments of the prehistoric record than with continuously recombining types within a more fluid concept of tradition.

Huffman is emphatic about the connection between his archaeological units and societies observed by ethnographers, stressing that although many elements of an ethnographic unit may be lost in the archaeological record, the patterned behaviour represented by ceramics ensures that the archaeologist holds the key to societal identification (Huffman 1971, 1974b, 1978). Thus "the traditional ceramics of different people in southern Africa today can be distinguished by the unique way each group combines the various modes of the dimensions of decoration, decorative layout and vessel shape. These stylistic types produce a definable decoration theme which cross-cuts functional boundaries, and the decoration themes of archaeological units can be determined by a simple analysis of the same three dimensions" (1979a:233).

Ideally, one would expect ethno-archaeological investigation of the precise relationship between social variables and patterning in ceramic decoration but this has not been undertaken. Huffinan (1980) has indeed applied a full range of analytical techniques to modern ceramic collections, but this cannot be considered a test of the underlying assumptions as the different communities were chosen precisely because they made differing ceramics. Other testing seems to have been limited. Thus, in his original discussion of Leopard's Kopje ceramics, Huffman (1968) refers in passing to ceramics made by Tonga villagers, suggesting that shape must be a primary unit of classification. This statement was later followed by an analysis of Shona pottery from a township near Bulawayo, with the aim of establishing potters' types as a basis for archaeological classificatory systems. Apart from some anecdotal information from other fieldworkers, the basis of this study was interviews with ten potters working in a market-orientated economy (Huffman 1972a).

The ease with which Huffman has drawn an equivalence between past and present, and his apparent lack of priority for the thorough testing of the interpretative assumptions that he has made, suggest that, like earlier archaeologists of the Iron Age, Huffman has assumed that the 'ethnographic present' also serves as explanation of the past. This is further evidenced by the laconic statement that the 'cognitive pattern' of the Bulawayo potters was




not complex and "should be applicable for at least African Iron Age societies and recent agriculturalists, for until the advent of the European, there has probably not been any major change in economy and technology by Iron Age people for 2 000 years" (Huff- man 1972a:78).

For Huffman, there is a further connection between ethnography and archaeology in the elements of language and the modes and types of ceramic assemblages, which he sees as 'behaving' in similar manner; a return in effect to the linguistic emphasis employed earlier by John Schofield. Thus Huffman (1970) considers linguistic and ceramic evidence in tandem on the basis of the feeling that their diversification had much in common. Furthermore, he implies that ceramics could provide evidence for language, by referring to 'proto-Bantu pottery' and 'PB-B', or 'Eastern Bantu' pottery. Huffman continued to develop this connection in later work, suggesting that it should be possible to find a connection between a linguistic dialect and a ceramic group (1971), that the diversity of southern African Iron Age ceramic traditions indicates that the diversification of the eastern Bantu languages had taken place north of the Zambezi (1974b) and that the Leopard's Kopje Tradition, renamed the Kutama Tradition, represents the spread of the Shona language northwards into Zimbabwe (1978).

Thus Huffnan's work shows a progressive modification of American theory to conform with the southern African ethnolinguistic record, replicating the earlier influence that ethnography had in reinforcing the assumptions of the British culture model. Such modifications are instructive demonstrations of the manner in which a specific intellectual environment can affect a discipline such as archaeology. In that none of the theoretical modifications are presented in any formal manner or are even explicit, Huff- man's work also attests the need for critique, for without assessment it is clear that subjective influence can be presented as objective 'fact'.

Analytical Implications: the Case of Kutama Apart from its effects on interpretation, the problem of the sub-

jective presented as established fact extends to Huffnan's approach to the analysis of data, for the assumption that there is a 'descriptive domain' leads to the assertion that the structure of an analysis can be independent of theory. To demonstrate this point I have chosen Huffman's (1978) case for establishing a Kutama Tra- dition. This paper is one of the fuller expositions of Huffman's methods of analysis and also a major revision of the southern African Iron Age sequence which has not so far been evaluated.

Huffman's method of analysis, which in a later paper he termed the 'multidimensional list' (Huffman 1980), is as follows. The in- put is a set of 'core concepts', defined earlier in this paper, which are divided into the categories of vessel shape, decoration (defined on the basis of geometric pattern, size and use in a band or pan- el), layout (consistent combinations of decoration), placement (the position of layouts on vessels) and technique (vessel colour and method of decoration). Huffman does not discuss the derivation of the core concepts which are presented as given (Huffinan 1978: figs. 2, 3, 4). Samples for analysis were either large single assemblages or combined assemblages from sites in the same area. The ceramics in each sample were examined and their core concepts determined. Because of the problems in comparing percentage counts between samples of different sizes, Huffman then convert- ed each sample analysis into a set of weighted scores. Thus a core concept that was not consistently present in the sample scored 0, a concept that was numerically low (which Huffman defined as about 10%) but consistently present scored 1, while a 'dominant concept', with a frequency of around 30%, scored 10.

In the second stage of his analysis, Huffman listed the weighted scores for the core concepts in each sample, and then calculated the degree of similanty between each pair of samples. This degree of similarity, called 'in', was expressed as a percentage and was derived by dividing the sum of the 'common score' of each pair of samples by the sum of the 'maximum possible common score' of each pair. The common score for a pair of core concepts was defined as twice the lower score. In other words, if samples P and Q have weighted scores for core concept x of 10 and 1, then the common score will be 2 and thle maximum possible common

score, 11. The degree of similarity, m, between samples P and Q measured by core concept x alone is 18%.

From the matrix of values for m obtained between all pairs in each set of samples, Huffman moved to the third stage of analysis. There is no definition of what constituted a significant value for m, but where there was a clear difference between one rn-value and the rest of the matrix, Huffman assumed a straightforward correlation to be demonstrated (for example, Hufftnan 1978: table 2 and map 1). Where there was more than one high in-value in the matrix, Huffnan employed an intermediate step to define the group- ings, performing what he termed a 'two-way clustering'; a two dimensional analysis of the distribution pattern.

The calculation of these two-way clusterings is the most obscure of Huffman's manipulations. The axes in Huffman's figures are not calibrated, but it would seem that he placed each point by transforming each in-value with the formulation 100-m and setting the coordinate position by calculating the relative distance of the sample to be plotted from the samples that define each end of the axis. Thus with an axis defined by samples P and Q, and with m- values between P and R of 75% and between Q and R of 45%, the distance of R from P is 100-75 = 25 and the distance between Q and P is 100-45 = 55. Therefore along the axis P/Q, a coordinate for R can be placed by the ratio 25:55, or at the value 3 on a scale where P is at zero and Q is at 10. The second coordinate is determined by repeating the procedure for the second axis.

Although Huffnan promoted his multidimensional list as an objective approach to the quantification of assemblage variation, a close examination of the method shows that completely subjective, and usually unexplained, decisions were taken at every stage. Thus there was an initial circularity in the choice of sample composition. Many of the samples consisted of several assemblages from 'contemporary sites', yet many of the sites listed do not have radiocarbon dates. Contemporaneity must therefore have been established on the basis of ceramic similarity - hardly a good crite- rion if the purpose of the analysis was to test for ceramic similarity. There was further subjectivity in the choice of core concepts, which must have owed much to the personal opinion of the classifier.

The confusion of relative and absolute dating and the failure to define variables are perhaps common problems in archaeology. What is more interesting, in the context of this critical examination, is the manner in which Huffman has incorporated subjective decision into the very fabric of his unique method of analysis. This is first evident in the system of weighted scores for the occurrence of core concepts. Huffman justified this device on the grounds that it eliminates percentage bias between samples, but this is illogical, since a system of weighting could just as easily accentuate percentage bias. More significant is the emphasis that this method gives to a small group of core concepts within the larger set that defines each sample. Thus core concepts w and x, for example, with frequencies of 10% and 30% and thus distinguished by a factor of three, will score in Huffinan's analysis 1 and 10 respectively - a tenfold distinction.

This accentuation is further strengthened by the method used to calculate the degree of similarity - in - between pairs of samples. Clearly the value of in is largely determined by the size of the common score, for the closer this is to the maximum possible common score, the higher the percentage value for m. But the common score is calculated as twice the lower of the weighted scores for each pair of core concepts, with the result that a high common score can be achieved by a pair of samples with a few heavily weighted 'dominant concepts' in common, but little else.

A final selection of emphasis comes in the presentation of the two-way clustering. In most of Huffmnan's sets of samples, there are many possible pairs of dimensions that could be chosen for this analysis and it is unfortunate that Huffman does not describe his criteria for this decision. Comparison of the maps giving the geographic distribution of the samples with the two-way clustering diagrams, however, suggests that Huffinan chose dimensions that ran acros the geographic distribution of the samples and were defined by samples falling on opposite extremities (for example, Huffinanl 1978: fig. 5, map 2). From the two-way clustering diagrams, Huffinan identified those samples that can be linked to-




gether; information that provided the basis for his reinterpretation of the southern African Iron Age. The selection of samples that fell on the geographical periphery of Huffman's areas of interest, however, allowed tendency towards clustering between them to be suppressed and clustering between samples that fell towards the middle of the geographic distribution of samples correspondingly to be emphasized. As with the use of ceramic similarity to define samples, the process is circular, for by selecting axes by geographic criteria, Huffman insures that the geographic criteria will be reflected in the cluster analysis. In addition, the use of only one of many possible pairs of axes may create spurious clustering.

The subjectivity of Huffman's method of analysis can be further demonstrated by working through a set of data. Unfortunately, Huffman does not provide any raw frequency figures for his samples, and so I have made use of a fabricated set of five samples, assigned random coordinates in a geographic area called Swam- pland (Fig. 1). To make the demonstration less complicated, I have assumed that each sample is of the same size, and that each can be descnbed by only five core concepts (Table 1).

An~~~~~~~~~~~~A

. 2

km~~~~~~~~~~~~~~~~~~~~k

Fig. 1. Swampland ceramic analysis. Geographical distribution of samples 1 - 5 by pairs of random coordinates.

The next stage in analysing the Swampland samples Ls to convert the frequencies in Table 1 to weighted scores. Unfortunately it is difficult to follow Huffman precisely here, as he does not specify the range of frequencies that would be considered for each score. I have assumed that a frequency of more than 20% will entitle a score of 10 and a frequency of between 1% and 20%, a score of 1. The consequent scores for our set of ceramic samples is given in Table 2.

I have argued earlier in this paper that Hufmfian's system of weighting can give emphasis to a few core concepts that are not necessarily dominant in the sample as a whole. In order to illus- trate this I have calculated values for 'in' for both the weighted scores in Table 2 and the straightforward frequencies in Table 1. Common scores, maximum possible common scores and in-values for these data are shown in Tables 3 and 4. Comparison of the

Table 1. Swampland Ceramic Analysis: Frequency of 5 core concepts, A-E, in 5 samples, 1-5.

SAMPLES

1 2 3 4 5 C A 30 45 23 0 40 N B 0 6 10 23 7 C C 0 14 30 21 25 E P D 25 35 30 32 28 T E 45 0 7 24 0 5

100% 100% 100% 100% 100%

Table 2. Swampland Ceramic Analysis: Scores for core concepts, weighted with the values 1-20%, 1, above 20%, 10.

SAMPLES

1 2 3 4 5 o A 10 10 10 0 10 N B 0 1 1 10 1 E C 0 1 10 10 10 P D 10 10 10 10 10 T E 10 0 1 10 0

30 22 32 40 31

results demonstrates the effects of weighting. In the first place, there are changes in ranking, for whereas the highest m-value for the unweighted data was for the sample pair 2/5, followed by sample pairs 3/5 and then 2/3 and 3/4 with equal readings, the highest m-value for the weighted scores was sample pair 3/5, followed by 2/5 and 213. Secondly, although the overall trends in the two sets of m-values are the same, the differences are far more accentuated for the weighted data. Thus whereas the unweighted data have a range of 49 to 88 and a standard deviation of 64 +-14, the weighted data have the wider range of 39 to 98 and the larger deviation around the mean of 70 +-17.

Table 3. Swampland Ceramic Analysis: Common Scores, maximum possible common scores and M-values using data in table 1.

Samples Common Score Max. Poss. Score M 1/2 110 200 55 1/3 110 200 55 1/4 98 200 49 1/5 110 200 55 2/3 146 200 73 2/4 104 200 52 2/5 176 200 88 3/4 146 200 73 3/5 166 200 83 4/5 112 200 56

Table 4. Swampland Ceramic Analysis: Common scores, maximum possible common scores and M-values using weighted values in Table 2.

Samples Common Score Max. Poss. Score M

1/2 40 52 77 1/3 42 62 68 1/4 40 70 57 1/5 40 61 66 2/3 44 54 81 2/4 24 62 39 2/5 44 53 83 3/4 44 72 61 3/5 62 63 98 4/5 42 71 59

The final stage of the analysis involves the definition of significant groups of the in-values, using Hufi~nan's technique of two- way clustering. I have argued that this method further modifies the results by an unstated predilection, for by choosing axes that link the geographical boundaries of a set of samples, correlation between samples at the boundary is suppressed. Reference to Fig.




1 will show that samples 2, 4 and 5 fall on the boundaries of Swampland, and so I have followed Huffman and performed a two-way clustering with the axes 2/5 and 5/4. The result, shown in Fig. 2, indicates a strong association between samples 3 and 5 which can now be said to represent the Swampland A Tradition, with the geographic distribution indicated in Fig. 3.

2 X2

x1

X4

X3 5 X5

4

Fig. 2. Swampland ceramic analysis. Two-way clustering of samples in Table 4, with the axes 5/2 and 5/4.

.2

..- / t

.4

@5

Irk~~~~~~~~~~

N

o 5

Fig. 3. Swampland ceramic analysis. Geographical distribution of samples, showing clustering derived in Fig. 2.

Choice of different pairs of axes, however, may have interesting results. Fig. 4 shows a two-way clustering with the axes 113 and 115. The Swampland A Tradition is still reflected in the top right- hand corner of the diagram, but it is now joined by a second association, almost as strong, which can be called Swampland B. In Fig. 5 the situation has changed yet again, for with the axes 3/1

and 3/5, the existence of the Swampland A Tradition is no longer sustained while Swampland B holds the field alone. Reference to the rn-values in Table 4, however, shows that whereas the now disintegrated Swampland A Tradition was supported by the earlier stage in the analysis, the ceramic samples 2 and 4, which make up Swampland B, have the lowest measure of similarity of all the possible pairs in the analysis. The point here is not that there are no strong associations in the in-values given in Table 4, for casual inspection shows that there are several high readings. It is rather that, even for a fairly small set of samples such as those from Swampland, there are 45 possible pairs of axes and therefore 45 possible two-way clusterings of which no single solution is necessarily 'right', as Huffman seems to assume. Some form of multidimensional clustering is essential to sort even a modest matrix of in-values into a meaningful pattern of associations (see for example, Hall 1981, 1982).

3 | I SWAMPLAND

SWAMPLAND

X4 B X2

1 Xi 5


xi

SWAMPLAND X21

[T 4 B

X5 3 X3

5


Conclusions Two main points may be made from this examination of the

American influence on southern African Iron Age studies and from assessment of Huffman's work in particular. In the first place, it should be clear that concepts in a discipline such as archaeology are modified by the intellectual environment of the ob- server - the separation of analyst from object of analysis is not as simple as is sometimes assumed. This does not in itself imply a value judgement, for to relate the study of the past to the problems of the present may be useful. Nor do I assume that critique can itself produce some value-free insight into the nature of contemporary Iron Age research, for it must be expected that the form that critical assessment takes is itself a product of the world- view of the critic. The point is rather that commentary is necessary if a full assessment of the value of research is to be achieved.




The second point is that belief in the absolute existence of facts leads archaeologists into a common empirical trap. For if the existence of 'descriptive domains' and 'real classifications' is assumed, it is easy to believe that such natural order can be discerned, with statistical methods, impartially and absolutely. In this frame of reference, critique becomes irrelevant, allowing the possibility that unstated selective processes are interposed in the analysis. I have suggested that Huffman's important examination of southern Afri- can Iron Age ceramics demonstrates this process, for, behind the shield of assumed objectivity, he introduces a series of modifications to the data that bring the value of the whole analysis into doubt. Thus the origins of the Leopard's Kopje Tradition, be-

lieved by earlier writers to represent a movement of people from the north, is completely reversed on the basis of an association between two ceramic samples. The composition of these samples is unstated, the core concepts that describe them are undefined, the weighting of frequencies and the calculation of the index of similarity distort the data and the clustering given is but one of many possible permutations. There may well be an instructive association between Bambata and Lydenburg ceramics, but it is not demonstrated by Huffman's analysis, which is rather the equivalent of suggesting, on the basis of partially described docu- mentary evidence, that the Pilgrim Fathers colonized England.

HYPOTHESIS EVALUATION: A REPLY TO HALL

THOMAS N. HUFFMAN Department of Archaeology, University of the Witwatersrand Johannesburg, 2001

Perceptive assessment of archaeological hypotheses is always a welcome contribution to the discipline. Regrettably, Hall's critique fails to make such a contribution because the two points he em- phasizes - origins of ideas and 'a personal point of view' - are irrelevant to the validity of any hypothesis. What is relevant, according to most philosophers of science, is the initial plausibility of an hypothesis in terms of general theory and then its explanatory adequacy and predictive potential in comparison to a competing hypothesis (see for example Copi 1968; Hempel 1966). Hall does not assess any of these essential criteria, he does not offer alternative interpretations and the framework of his critique - an ill-defined dichotomy between British and American archaeology - only clouds the debate further.

Besides a concern with irrelevant issues, Hall's critique is super- ficial. I show first that he is wrong about the theoretical position that I and others such as Dunnell hold and, secondly, that these errors lead to misdirected criticism of my core concept paper.

I

I do not assert, as Hall claims, that "the structure of an analysis can be free of theory." In fact, I have said just the opposite (Huff- man 1980:125):

Ceramic analyses represent the application of specific theory to data, and a formal analysis can be said to have three components: (A) theory - the choice of variables for a specific purpose; (B) procedure - the formation of variables into types; and (C) comparison - the calculation of relationships between samples.

Hall also misrepresents my position when he credits me with the "feeling that 'real' classificatory systems. . . will have been found when the archaeologist succeeds in matching his classifications with those employed by prehistoric communities." I believe something quite different (1980:124):

All classifications are arbitrary abstractions in that only certain variables are used, otherwise every artefact would be a unique type. Furthermore, all classifications should have a purpose, and there can be as many different classifications of the same data as [there are] purposes. Since every variable has a distribution pattern, classifications are neither true nor false; they are either useful for a specific purpose or they are not.

I have never believed that emic classifications were 'real', but I did once claim (Huffman 1972b) that emic types were the best kind if the purpose of the classification was to connect archae-

ological cultures with existing peoples. That claim, of course, was simply wrong. I later found that size categories were difficult to determine, even with assemblages of almost complete vessels (1976:31), and I subsequently (1979b:38) rejected the emic position and eliminated function entirely because it was unnecessary. From the points of view of abstraction and purpose, emic classifications are no more 'real' than etic ones.

There is one sense, however, in which classifications can be said to be 'real' and that is in the sense of validity. If classifications are seen as hypotheses about how archaeological data are patterned, then it is unlikely that two classifications for the same purpose can be equally valid: one will 'explain' more data and have greater predictive potential than the other. Since humarn behaviour is patterned, there has to be order in the archaeological record independent of the archaeologist, and it can be discovered, or at least approximated, through the normal testing procedures of the human sciences. I presume Hall has not considered this other mean- ing when he criticizes "the belief that classifications are inherent in data, rather than devices dependent on research problems", for these two statements are not mutually exclusive. If an order independent of the archaeologist did not exist, no one interpretation would be better than another, and we would be wasting our time. In any case, a belief in such an independent order does not mean that "critique becomes irrelevant" to me, as Hall asserts in his last paragraph: testing procedures are the only means of establishing validity.

Hall misjudges my position on 'real' classifications, theory and testing because of a misinterpretation of Dunnell (1971). Hall mis- takenly thinks that Dunnell's distinction between ideational and phenomenological realms is the same as the classical empiricist's belief in a world of facts free of theory. These are two separate issues. Dunnell (1971:26) says:

By dividing analytically all 'things' into phenomenological and ideational realms a number of important sources of confusion and error can be avoided. It is important to remember, however, that this and any other distinction are artificial. They do not say any- thing about the real world, whatever that may be; they are designed for a purpose - to facilitate scientific enquiry - and nothing else.

Dunnell's division merely reflects a standard position in science that concepts about data are not the same as the data themselves and that definitions should not be tied to empirical examples - in other words that definitions should be 'contingency free'. If, for example, the definition of a hunter-gatherer way of life was corre- lated with the Bushmen, rather than defined solely as a subsis- tence mode, hunter-gatherers could only exist or have existed where there are or have been Bushmen, rather than anywhere at

S. Afr. archaeol. Bull. 38: 57-61. 1983



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Tribes, Traditions and Numbers: The American Model in Southern African Iron Age Ceramic Studies

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