DEALING WITH TIME IN ARCHAEOLOGY: A PROPOSAL

The debate regarding the concept of time reveals that time does not exist as an autonomous physical entity which can be observed, described and measured. What exists is the evidence of change, while time is merely a dimension within which we operate, rather than a separate entity that exists independently of the archaeological record.

Archaeologists do not have access to the social actions that generated the changes observed in the archaeological record. Archaeologists deal with the so-called “reverse problems”: we aim to infer the causal mechanisms which produced the observable archaeological record. However, the archaeological record is not a chaotic aggregation of isolated, unconditioned and arbitrary events without any connection. The generation of material entities involves a process consisting of a sequence of successive actions and states. For example, the cause of the existence of a table is not that a board is related to four wooden legs, but that at a certain moment, a carpenter placed a specific board (produced beforehand) on particular wooden legs. Therefore, the carpenter’s work is the cause of the existence of the table, and the temporal process is constituted by the sequence of work actions during which a board was placed atop wooden legs (Barceló 2007 & 2009):

The goal of archaeology is to explain the path of the observed changes, ordering them in a sequence according to the specific characteristics resulting from the causal process generating such changes. The explanation of this trajectory is the explanandum of what happened in the past. In other words, archaeological research can be defined as the study of the invariabilities and changes in the archaeological record in relation to three different dimensions (time, space and materiality) and how these changes were produced or reproduced by social actions (Barceló 2009; Barceló et al. 2005).

The existence of an archaeological artefact is also an event, because at a precise time and place, it acquired certain properties such as a specific shape, size, composition or texture. This process implies that an earlier event must have taken place in an ordered sequence in which certain matter (defined by its characteristic traits) had been modified and had acquired other properties: it had changed (Barceló 2009; Barceló et al. 2014). In this way, answering a “when” question does not consist in simply giving a date, but instead in stating a relationship. The events must first be arranged in time order so that changes can be observed, and it is the order of changes that will answer the question “when”.

In this work, an event-based chronological analysis is proposed, based on the principle that an event should be treated as the analytical unit (Sewell 2005). However, the focus here is not as much on the temporality of a particular event as on the relationship between the temporalities of different events. As noticed by Buck (Buck & Millard 2004:5), if the objective is to measure the evidence of change, what must be done is to “take a collection of dates or temporal relationships for a series of individual events and combine them with other information to synthesise a chronology which may include the inferred dates of events for which no direct dating evidence is available”. In this sense, dating history should be understood as an analytical process involving the formalisation and structuring of different data sets, in order to define events and their causal relationships (Barceló 2009;

Barceló et al. 2013).

However, how does one arrange events into a sequence? One of the main problems is that we infer our chronologies from indirect proxies, such as the spatial location where the artefacts were found (stratigraphy), their physical properties (the number of 14C atoms they contain) or their stylistic or technological features (their particular decoration or techniques used). Thus, when dealing with temporality, we deal with variables that are not directly related to time. Unfortunately, this is the reason why our time estimations tend to be imprecise and uncertain, constantly revised and subject to updates. As said by Enrico Crema (2012:442), “our knowledge of time is heavily dependent on such continuous and perhaps never-ending updates”.

In addition, and for more uncertainty, the artefacts through which we intend to date an event were found together with the target object (dating an associated charcoal to a level of collapse, for example) (Dean 1978). This implies that the depositional processes should

be taken into account when we try to determine the temporality of an archaeological context or phenomenon. Different quantitative solutions have been proposed (for example, Bellanger et al. 2008; Buck & Sahu 2000 or Buck et al. 1992). Unfortunately, there is no universal solution, so the depositional processes continue to be a factor of uncertainty when establishing chronologies.

The nature of the archaeological record forces us to work with all these uncertainties.

Although they cannot be eradicated, they can be identified in order to evaluate the degree of reliability of our sequences. In this work, it is proposed that the quantification of time, space and all the relevant information related to the event (and its context) are a useful tool to control and measure these uncertainties. If the data is uncertain, working with probabilities will be required. The purpose of a chronological analysis is thus to estimate the probability that some event started or ended at a particular moment in time (Doerr et al.2004). As will be discussed in more detail in the next chapter (chapter 3: Methodology), if arranging a group of events into a sequence implies uncertainty, determining their chronology involves testing a statistical hypothesis, rather than making a direct inference (Bayliss & Bronk Ramsey 2004; Bayliss et al. 2007; Steel 2001).

2.4. DISCUSSION.

In this chapter, an attempt has been made to highlight the importance of the conception of time when analysing and interpreting the past. Time does not exist. What we really perceive is the passing of events that we relate to one another through successions or overlaps. Time is a convention that facilitates the measurement of changes. Answering a

“when” question does not consist in simply giving a date, but instead in stating a relationship, a change.

From this ontological point of view on the notion of time, an event-based chronological analysis has been suggested, whereby an event is to be regarded as the analytical unit. The main idea of the chronological analysis should be to determine the relationship between the temporalities of different events, that is, between changes. Unfortunately, our chronological estimations tend to be imprecise, uncertain and subject to constant updates, because we infer them from indirect proxies, while the palimpsest character of the material data and post-depositional processes must be taken into account.

In view of this reality, the quantification of time, space and the archaeological data is proposed here as a way to control and assess these uncertainties. Owing to the nature of the empirical record, the results that can be obtained are likely to be probabilistic rather than definitive, as much with respect to continuities and changes, as to the chronological sequences of the archaeological record.

In the next chapter, the methodological aspects of this work following the principles set out here will be covered. It will be explained in concrete terms how these uncertainties have been addressed, both in terms of the type of data used and the way this data was collected and analysed. As mentioned above, the main idea is that the chronology of an archaeological event should not be understood as an absolute entity, but rather as an inference process that integrates different kinds of information with a view to drawing the best possible conclusion from the available data.