Guide – Critical Thinking: Lack of Evidence Does Not Mean Evidence of Lack

“Lack of Evidence Does Not Mean Evidence of Lack”: Critical Thinking and the Dangers of Assumed Knowledge

In archaeology, the phrase “lack of evidence does not mean evidence of lack” is an important reminder that the absence of proof does not necessarily prove something does not exist or did not happen. In fact, this statement touches on a subtle but pervasive issue in the field of research: the tendency for researchers—whether archaeologists, historians, or even students—to fill in gaps with assumptions. These assumptions often arise from biases, preconceived notions, or the overwhelming need to find patterns and explanations that make sense with the evidence we do have. However, this can lead to gaps in knowledge that become overlooked, misinterpreted, or even “brainwashed” into being accepted as truth.

The Brainwashing of Assumptions and Pattern Recognition

One of the key issues in critical thinking is recognizing that human brains are wired to seek patterns. It’s a survival mechanism: we look for connections between events or objects in order to predict outcomes. In archaeology, this can be a double-edged sword. While pattern recognition is vital for understanding the past, it can also lead to errors.

Let’s say an archaeologist is excavating a site and finds a series of objects that appear to form a pattern—such as pottery shards that align with a particular period of time. Based on this, they might begin to assume that they are dealing with a continuous or settled site. However, if the excavator doesn’t pause to question that assumption, they may overlook the possibility that the pottery could have been deposited at different times, or the area could have served multiple purposes over time. The mere lack of evidence for long-term habitation in this case doesn’t mean the evidence doesn’t exist; it might simply not have been found yet—or it could have been missed due to the narrow focus on certain types of evidence.

Critical thinking in this context requires the archaeologist to remind themselves: “What am I assuming, and why?” This means that we must always stay aware that our minds are conditioned to “fill in the blanks,” but doing so without acknowledging the gap can lead to flawed conclusions.

In a report, we would want to address these gaps openly: acknowledging what we know and, just as importantly, what we don’t know. For example, in the context of a field system, instead of assuming that the absence of a clear water source means it wasn’t a valid field system, a critical thinker would write something like, “While there is no immediate evidence of a water source within the field system, it is important to note that water sources could exist beyond the excavation area, or might have been integrated into a broader landscape system that has yet to be fully uncovered.”

Such an approach not only demonstrates transparency but also shows patience and humility in archaeological research. It provides a space for the “lack of evidence” to be questioned rather than dismissed too quickly. In turn, this gives future researchers the opportunity to come back to the site, explore new ideas, or take a fresh look at previously unconsidered data.

The Dangers of Overly Rigid Interpretation: Bias in the System

In academia, we can see these biases manifest in various forms, such as students who overly criticize their lecturers’ interpretations, or place too much emphasis on the interpretations of an outsider. In a university setting, this behaviour can be attributed to several factors, including the pressure of imposter syndrome or the feeling of needing to demonstrate superior knowledge. Students might feel compelled to point out flaws in established interpretations to prove their own competence or to differentiate themselves from the group.

While it’s important to critically evaluate the work of others, especially in archaeology, over-criticism can stifle the spirit of collaboration. Students might find themselves dismissing expert opinions too quickly, focusing on what they believe to be “mistakes” or inconsistencies, even if these are just natural complexities or areas where evidence is still inconclusive. This leads to unnecessary conflict and hinders productive learning and discovery.

Moreover, the sense of imposter syndrome—feeling like a fraud in a professional setting—often leads researchers to hide mistakes or avoid admitting to gaps in their knowledge. They may overlook errors in their own work or, in the case of historical omissions, fail to question when something is being left out of the record. The drive to “fit in” with the dominant scholarly narrative or avoid rocking the boat can lead to the perpetuation of gaps in knowledge. This is especially problematic when one field of research builds on the conclusions of another without critically re-examining the premises.

Consider the example of historical omissions: When early archaeologists or historians, operating under the assumptions of their time, ignored or omitted certain pieces of evidence because they didn’t align with the mainstream narrative—such as the role of women or lower-status individuals in ancient societies—it wasn’t necessarily a deliberate attempt to obscure the truth. Rather, it was due to the dominant narratives of the time, which themselves were influenced by cultural biases and a limited understanding of the past. This type of omission can have lasting effects on the academic field, as those gaps in knowledge remain unchallenged for generations.

A modern-day equivalent might be the dismissive attitude some scholars may have towards unconventional interpretations of archaeological sites—perhaps due to the assumption that new methods or technologies can’t uncover what older methods missed. But if researchers do not continually re-evaluate data and assumptions, these gaps can widen, leaving crucial insights out of the historical record.

A Real-Life Example: The Misunderstanding of Stonehenge’s Construction

One example of “lack of evidence” leading to flawed conclusions in archaeology is the initial misinterpretation of Stonehenge’s construction timeline. For many years, the dominant theory was that the stones were transported over long distances using primitive methods, but the “lack of evidence” for these methods meant that many archaeologists simply accepted that we would never know the exact process. However, new evidence and more critical thinking challenged this assumption. More recent excavations and geophysical surveys revealed that local quarries were used to source some of the stones, demonstrating that assumptions about the construction process were incomplete, not necessarily wrong.

The long-standing belief that the stones were moved by a single, mysterious method persisted largely because the evidence didn’t seem to fit alternative explanations. This reluctance to challenge a long-held theory led to many years of incomplete or misleading conclusions. In this case, archaeology benefited from being patient and revisiting prior assumptions.

The Call for Patience and Openness

For critical thinking to truly be effective in archaeology (and beyond), we must adopt the approach of considering the whole picture—acknowledging that our own thinking, our own patterns, may not always lead to the right answer. We must openly admit that some conclusions are not fully supported by evidence yet and that we may not have all the data we need. By taking the time to question our own assumptions, and the assumptions embedded in prior research, we open the door for a fuller understanding to emerge.

In summary, when discussing gaps in knowledge or the “lack of evidence,” critical thinkers must avoid filling those gaps too quickly with assumptions. Instead, they should embrace the unknown with humility and patience, recognizing that in archaeology—just as in life—answers are often not as simple as they appear at first glance. By doing so, we can avoid the brainwashing of conventional wisdom and make space for new, potentially revolutionary insights.