Stibbard-Hawkes presents a much-needed case for distinguishing between different types of evidence for cognition (e.g., its complexity and capacities) in past cultures, arguing in particular (and rightly) that evidence of sophisticated materials may be evidence for the absolute capacity of a culture, but the absence of such evidence does not allow inferences about the absolute incapacity of the culture, and that both cases do not per se allow claims about comparative capacity (between different cultures). While the author's critique is compelling, he does not present an overarching approach for moving forward in making claims about the cognition of past cultures. In the present commentary, we present an initial model for calibrating both absolute and comparative claims about cognition in past cultures by examining the diversity, necessity, and complexity (DNC) of the material evidence for a culture.

The DNC-model proposes three decision heuristics or preconditions for calibrating claims about the cognitive capacity of a past culture on the basis of its material evidence. Note that we define this type of evidence for a culture as the set of actual objects found that are definitely or very probably related to the culture of interest. These sets of objects have three characteristics by which they can be distinguished and which can subsequently be used to navigate well-calibrated claims about the absolute and comparative cognitive capacity of a culture.

First, as shown in Figure 1, the set of material evidence that exists for a past culture can be judged by its diversity. That is, the material evidence may differ at several levels, for example, from different overarching aspects of life in that culture (e.g., family, politics, or religion), with different intentions (e.g., for pleasure, persuasion, or war), and from different generations of that culture (e.g., Roman kingdom, republic, and empire). The diversity of an assemblage determines how comprehensive the researcher's perspective on the past culture is, with material evidence from different aspects of life increasing our understanding of the culture. Subsequently, the diversity of the material evidence available for a past culture centrally determines the extent to which claims about its cognition can be generalized (across individuals of that culture and across generations of that culture).

Figure 1.

Calibration model to navigate claims about absolute and comparative cognitive capacity of a culture.

Second, the set of material evidence may include objects that are both necessary and unnecessary for a given culture. Specifically, highly culturally necessary material evidence is that which fulfills basic functions and needs in every, or at least the vast majority of, cultures, such as certain tools for obtaining and preparing food, or for creating shelter in the form of clothing and architecture. Comparatively culturally unnecessary evidence consists of objects that are more selective and not in themselves generally integral to a culture, such as religious objects (e.g., figurines depicting mythological or spiritually charged entities, such as the German Hohle Fels Venus, Conard, Reference Conard2009; and the Hohlenstein-Stadel lion man, Hahn, Reference Hahn1986; Wynn, Coolidge, & Bright, Reference Wynn, Coolidge and Bright2009) or objects for certain pleasurable activities (e.g., bone flutes for producing certain melodies; Conard, Malina, & Münzel, Reference Conard, Malina and Münzel2009). The overall level of necessity represented in the material evidence set of a past culture determines the extent to which researchers can make comparative claims about that culture being more or less cognitively sophisticated than other cultures.

Lastly, the assemblage of material evidence for a past culture may exhibit a range of complexity in its objects at different levels. For example, objects may be complex in how they are made (e.g., copper tools vs. pure flint, or bow and arrow vs. a simple spear) and complex in what they are intended to do (e.g., a bone needle for filigree sewing or a plough for sophisticated agricultural activity). The peak of complexity in the set of material evidence can guide our inference about the past culture's potential for cognitive complexity or cognitive capacity.

Importantly, the first two features or decision heuristics (diversity and necessity) of the DN(C) model can be used as a more general model for calibrating absolute and comparative claims about a past culture. That is, any cultural inference that can be derived from material evidence can be combined with judgments about the diversity and necessity of the objects included. This makes it possible to calibrate (a priori) or confirm (post hoc) claims about a variety of characteristics of a past culture other than its cognition, such as religiosity, value systems, or political perspectives. To investigate claims about these other cultural traits, the only one of the three traits to be replaced in the present model would be the third and final trait that directly evaluates the objects in a set of material evidence for the specific trait in question (i.e., in the present commentary, complexity as a proxy for cognitive capacity).

The proposed model is differentially effective in achieving a better understanding of past cultures for different cultures. Most importantly, our object-based model becomes more applicable as the alternative methods that could be used to measure the desired feature claim of that culture become increasingly scarce. For example, for the Mediterranean cultures of classical antiquity, the abundance of surviving architectural, pictorial, epigraphic, and especially literary sources often allows for a more precise assessment of the desired feature claim than the more basic archaeological evidence (e.g., pottery, tools, etc.) alone could provide. We hasten to point out that the DNC model is of considerable relevance to the Middle and Upper Palaeolithic, which is Stibbard-Hawkes's main focus, where there is an almost total lack of other such sources as outlined above.

Stibbard-Hawkes opens up a central discussion about what kinds of evidence and lack of evidence allow for what kinds of (absolute and comparative) claims about past cultures. To make a first productive proposal for a unified framework for calibrating and corroborating such claims, we present the DNC-model, which is based on evaluating two core features of a set of material evidence (i.e., object diversity and necessity) and one feature specific to the cultural characteristic of cognitive capacity (i.e., object complexity). This model allows researchers to propose and discuss which claims about a past culture are robust and which are tentative at best.