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Science is written by Sebastian Payne

Pitt Rivers included detailed “relic tables” with his excavation reports

English Heritage’s chief scientist, who has seen more excavations and laboratories than most, ponders the place of science in archaeology RememberPittRivers: archaeology is science

We have learned an enormous amount from the application of scientific techniques to archaeology, especially over the past 50 years. Among the more important of these, geophysics and remote sensing help us find sites and start to understand them without digging. Radiocarbon and other dating methods have given prehistory a secure framework. X-radiography and analyses of artefacts tell us about how and where they were made. And stable isotope analyses of human remains help us to reconstruct diet, and movements of people between different areas.

But the past 50 years have also seen an increasing separation between what is perceived, perhaps, to be “mainstream archaeology”, and what is often called “science-based archaeology”. Archaeologists have started to lose sight of the importance to their field of the basic scientific approach to finding out about things. What lies at the core of science-based archaeology is not machines and equations, but the way science deals with evidence. Science does not just round up information, use it to come up with a plausible conclusion and present this as an established truth. Instead, it tries to think of as many reasonable explanations for the available evidence as possible, then eliminates them to leave the simplest remaining explanation as a provisional conclusion, using an explicit chain of reasoning and data.

This has two important consequences. Explicit chains of reasoning and evidence provide the basis for discussion and development. Provisional conclusions become the starting points for better future understanding, rather than defended positions which act as barriers to new ideas.

Archaeologists in the late 19th and earlier 20th centuries, like Augustus Pitt Rivers, Flinders Petrie, Mortimer Wheeler and Kathleen Kenyon, understood this well: they saw archaeology essentially as another of the observational sciences, like geology or natural history. They emphasised the careful and methodical gathering and documentation of evidence, as for instance in Pitt Rivers’ published “relic tables”, which helped him act “upon the principle of reasoning from the known to the unknown”.1 They were careful to make sure that conclusions were clearly based on the evidence – as they saw it – and did not go beyond it.

It is important that archaeologists get more comfortable with science again. Like a new camera or washing machine, most scientific methods are basically simple enough once they become familiar. If archaeologists do not understand – at some level – the methods and kinds of data on which archaeological scientists base their conclusions, they cannot assess their reliability. Without this understanding, the risk,

One of Pitt Rivers’ best known excavations, at the prehistoric Wor Barrow, Dorset and often the reality, is that scientific conclusions are taken as established facts when they fit with pre-existing belief, or rejected when they do not, rather than being judged on the quality of the evidence. Neither acceptance nor rejection in this way is good for archaeology: they lead all too often to wasted effort and missed opportunity. Archaeological scientists often add to the problem by not engaging enough with mainstream archaeology, and not understanding the nature of archaeological evidence – far too few archaeological scientists get out on sites and dig.

But it is even more important that archaeology rediscovers its origins as an observational science, with conclusions explicitly based on evidence, and always treated as provisional. Of course, we should continue to speculate beyond the available evidence – this is often a good way to trigger new questions. But we need to be clear – to ourselves and to our audience – when we are doing this.

Thanks to Terry O’Connor for – as always – interesting discussion

More science 1 Catalogue of the Anthropological Collection Lent by Colonel Lane

Fox for Exhibition in the Bethnal Green Branch of the South Kensington Museum June 1874, by Colonel Lane Fox (HMSO 1877); Excavations in Cranborne Chase vols I–IV, by AHLF Pitt Rivers (Pitt Rivers 1887–98)

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