Explaining the Past

In light of the above discussion, it is clear that only scientific and historicist archaeology ‘explain’ past human behavior as traditionally understood in the philosophy of social science. Historicist archaeology explains the empirical record by placing objects, monuments, and texts in their historical context. Scientific archaeology views explanation as a logical reductive process. Historicist archaeology, in turn, focuses on what was once known as space-time sys-tematics; this is the locating and explanation of objects in an ordered sequence around the world in different places and times.

There are a number of logical means by which archaeologists seek to explain the past. Perhaps the most common is the ethnographic analogy. Ethnographic analogy is based upon the principle that people in similar cultural and environmental circumstances faced with similar goals, resources, and constraints will behave in similar ways. Ethnographic analogy works best where the consequences of failure to obtain the desired goals can result in death or extinction of the individual or group. In these instances, it is assumed that optimal solutions will independently develop among peoples in space and time, irrespective of any kind of cultural meaning associated with those solutions. Suboptimal choices will be selected out in any competitive environment. Examples here include defensive constructions, irrigation agriculture, hunting techniques, and the like. While there are many ways to protect a group of people against another group in a premodern context, there is a very limited set of optimal choices given the iron logic of war and extreme consequences of failure (see Arkush and Stanish (2005) for examples of this logic with premodern military architecture). Therefore, around the world in space and time and effectively independent of cultural factors, premodern fortresses are strikingly similar in architectural style and function. Likewise, given the invariant laws of the physics of water movement, there are very few successful ways to construct irrigation systems. As with defensive architecture, irrigation works around the world in similar environments tend to be very similar in design and use.

Given this, and given the precept of parsimony, archaeologists can make high-probability interpretations of the function and use of irrigation systems, defensive architecture, and other such features in the archaeological record, even without any textual information. Ethnographic analogy works with other kinds of human behavior to varying degrees. It is successful to the degree that selective pressures operate on the choices made by people. Where cultural choices, such as language syntax or dress styles, do not alter the fitness of individuals or groups in a selective environment (both social and ecological), then ethnographic analogy is of little or no use.

Ethnoarchaeology and experimental archaeology are logically similar to ethnographic analogy (see Ethnoarchaeology; Experimental Archaeology). Ethnoarchaeology studies modern peoples to provide more precise ethnographic analogs to aid in the explanation of past behaviors. Experimental archaeology seeks to replicate the behaviors by which archaeological data are created. Both rely on empiricist epistemological assumptions and the precept of parsimony. These two fields are simply formal procedures of ethnographic analogy used to derive analogs from the known record of human behavior.

The direct historical approach can be used with great success in a number of archaeological contexts around the world. The basis of the direct historical approach is that objects used by ethnographically documented peoples that are similar in key ways to objects found in archaeological contexts of those same peoples’ ancestors, carry a high probability of having the same function. Likewise, the adoption of the principle of parsimony is necessary. For this approach to work, there must also be a direct cultural relationship between an archaeological data set and a living group of people. Therefore, if one excavates a round structure with similar features to a historic hogan in Arizona, and if there is no evidence of cultural disruption, then one can make a high-probability statement that the excavated structure functioned in the same way as the historic hogan. The utility of the direct historical approach is proportional to the closeness in age and space of the archaeological and ethnographically known analog.

The comparative approach is often confused with ethnographic analogy and the direct historical approach. The comparative approach is epistemologically different, though it is often used in conjunction with ethnographic analogy by scientific archaeologists. What distinguishes it logically from ethnographic analogy is that the comparative approach is feasible only if one adopts some kind of broadly processual and evolutionary theory. A theory is only evolutionary in the modern sense of the term if it contains some kind of selective mechanism. Given this assumption, plus the assumption of parsimony, organizationally similar societies in similar environmental circumstances can be used as analogs to archaeological complexes.