Difference of epistemic perspectives between scientists and the lay public: Observations from a public debate on Pu’er tea

Abstract

As per conventional wisdom, scientists and the lay public differ in their epistemic abilities. Based on an analysis of a public debate on Pu’er tea, this paper emphasizes that there are differences between scientists and the lay public in their epistemic perspectives, including differences in attention, problem definition, criteria for judgement and reasoning. These perspectives may differ in degree and may switch or combine. This difference may explain the failure of communication between scientists and the general public. Thus, the success of such communication depends on overcoming the perspective paradox.

1. Introduction

In public policymaking, particularly in scientific affairs, communication between scientists and the lay public is important. Public dialogues are expected to become more common as a means to stimulate solid opinion forming based on a wide range of views (Reincke et al., 2020). However, such dialogue or communication does not always lead to a consensual result. A key reason lies in the epistemic differences between scientists and the lay public. The conventional view is that scientists and the lay public differ in their epistemic abilities. The deficit model supposes that the public is ignorant of science and has negative attitudes towards science and technology because of that ignorance (Ahteensuu, 2012). Although this model of communication is often considered essentially flawed, it persists among many scientists and science organizations (Simis et al., 2016).

Based on an analysis of the discourse between scientists and the lay public on Pu’er tea, this paper notes that scientists and the lay public also differ in their epistemic perspectives, and these differences are not absolute but may switch or combine. Thus, effective communication between scientists and the lay public depends on the convergence of their respective epistemic perspectives.

‘Perspective’, or ‘perspectivism’ as defined by Ron Giere (2006), is a concept used to explain scientific knowledge. Perspectivism denotes that, as people's epistemic capability and resources are limited, the process of scientific understanding inevitably relies on their epistemic characteristics and how they interact with the environment. For example, a person's vision system can respond only to a certain spectrum of electromagnetic waves. Likewise, scientific instruments are designed to respond to a certain range of information inputs. Therefore, we cognize things through our vision system using its characteristics and scientific instruments. When examining the brain through an instrument, what we see is not the actual brain but the image captured by a CT scanner or fMRI (Massimi, 2012). Scientific knowledge is historically and culturally embedded and a product of the contemporary mainstream culture, including scientific representation, model practice, data collection and scientific theory (Massimi, 2017). Perspectivism can explain a broad spectrum of cognitive activities. It permeates not only the epistemology of sciences but also the cognitive process in general. Laypeople's cognitive processes and results are also subject to the influence of their epistemic perspectives.

2. Epistemic perspectives of scientists and laypeople examined from a public debate on Pu’er tea

Pu’er tea is a variety of fermented tea produced in Yunnan. It can be divided into raw-tea and ripe-tea varieties. Both varieties must undergo a complex process of gradual fermentation and maturation, which can take decades.

In July 2017, writer Fang Zhouzi published the article ‘Is drinking tea anti-carcinogenic or carcinogenic?’ in a popular-science journal. The article cited several scientific papers and pointed out that Pu’er tea may contain aflatoxin, a highly carcinogenic substance. Later, the article was widely circulated on the internet and led to a public debate on Pu’er tea. Participants have included trained researchers and members of the general public. Each camp has exponents and opponents of Fang's view. Based on participants’ articles and comments, one is able to determine whether they were trained researchers or laypeople.

The analysis of their discourse finds that scientists and laypeople have some common aspects in metacognition, which reflects one's ability to monitor and control one's cognitive processes (Fleur et al., 2021) and commit to some shared cognitive norms. In explaining the failure of communication between scientists and laypeople, the term ‘mob mentality’ is often used to attribute the failure to laypeople's lack of knowledge and reasoning ability. However, the analysis of the debate on Pu’er tea shows that this attribution is inappropriate.

One of the reasons is that both scientists and laypeople consider facts to be important and require objective evidence to pass judgement. They all agree that the debate should not be adulterated by considerations of personal interests. For example, a scientist noted that an academic debate should be based on facts without regard for persons. What matters is only whether the reasoning is sound, rather than who says it or for what motive, because those factors have nothing to do with reasoning; otherwise, the debate becomes a quarrel. Because of this consensus, a lay reader can also make objective comments; for example, ‘This article focuses on facts and reasons scientifically. It lets monitoring data speak for itself and is therefore convincing, putting to shame those who base their views on rumour mills.’

Another reason explaining the inappropriateness of attributing unsuccessful communication to laypeople is that both scientists and laypeople may have flawed evidence and tend to choose evidence that works in their favor, and thus both parties may have such problems as overgeneralization and wishful thinking. For example, scientists and laypeople in support of Fang's view tended to discredit evidence offered by local scientists in Yunnan on grounds of their vested interests. However, those who opposed Fang's view suspected that he was promoting Oolong tea in Fujian (Fang is a native of Fujian, the main location for the production of Oolong tea).

From the discourse between the two groups of people, it can be seen that they differed significantly in their thinking. The differences can be examined from the following aspects.

First, scientists and laypeople differ in what catches their attention. Cognitive scientists have found that attention plays an important role in the brain's processing of information. Perception, thinking, learning, decision-making and action all require attention. Attention plays two important roles: as a filter that selects and admits channels of information from the environment to be processed; and as a resource to enable subsequent information processing, constrained by the individual demand of tasks (Wickens, 2021). Human cognitive resources are limited, so the brain can incorporate only partial information from the environment into consciousness while ignoring other information. Attention is paid to prominent features in the environment, but people vary concerning the prominent features that attract them.

The article by Fang initiated the debate on Pu’er tea. It contained information on various aspects, such as epidemiological studies on drinking tea and cancer prevention, clinical-trial results of drinking tea and cancer prevention, the relationship between drinking tea and cancer, and the relationship between how tea is made and stored and carcinogenic risks. However, scientists and laypeople involved in the debate differed in what aspects of the article attracted their attention. Scientists focused their attention on aflatoxin—whether the processing of Pu’er tea results in the production of aflatoxin, in what steps it is produced if there is any, and whether there are test results that prove the existence of aflatoxin in Pu’er tea. The lay public was concerned about whether drinking Pu’er tea was harmful to health, especially its potential carcinogenic effect, and the laypeople also considered what impact the circulation of the article would have on farmers growing Pu’er tea. Scientists and laypeople were not interested in the general conclusion of the article and tended to intentionally or unintentionally ignore the other information beyond their focus.

Second, scientists and laypeople differ in defining problem objects. One of the fundamental human cognitive processes is problem solving. When a problem object is identified, epistemic agents will search in the memory space and find a relationship between a set of solution goals and a set of alternative paths (Wang and Chiew, 2010). The debate on Pu’er tea involves two groups of people asking and trying to answer different questions.

Scientists, both those supporting and those opposing Fang's view, asked the same question: whether aflatoxin is produced in processing and storing Pu’er tea, and, if so, at what step in the process is it produced? Those who opposed Fang denied that aflatoxin would be produced in the normal stacking step of Pu’er tea. Concerning the stacking methods (including dry stacking and wet stacking), they considered wet stacking, which is often used by unscrupulous merchants to produce aged Pu’er tea quickly, as the method that may produce aflatoxin. By contrast, the laypeople had different questions. For example, they may ask: Should Pu’er tea be drunk at all? Who is correct, Fang or the opposing scientists? The questions depended on what aspects people focused on and their presumptions. Scientists often ask questions from within a clear reasoning framework and have ready tools or procedures to answer the questions. In contrast, laypeople often raise ill-structured questions. They have neither clear targets nor the background knowledge to answer their questions. More importantly, the answers offered by scientists cannot directly answer the questions asked by laypeople.

Third, scientists and laypeople differ in representations of their thoughts. Symbolic representations are essential for capturing human cognitive capabilities. Epistemic agents construct internal symbolic representations to capture the connections between different things in the world (Forbus et al., 2017). For a long time, people have realized that the way we represent the world also affects the way we think and what we think. In the debate on Pu’er tea, it is clear that scientists had a richer, more specialized way to represent their thoughts.

First, scientists have a shared conceptual system. Thus, in the debate, they could describe the temperature of the stacking step, distinguish between dry and wet stacking, and even describe subtle differences in terms of humidity and ventilation. However, laypeople's conceptual system was underdeveloped in comparison and mostly derived from the classification systems and experiences of everyday life. For example, laypeople could argue only in general terms with statements such as ‘Any food has a shelf life’ (implying that Pu’er tea stored for too long could be harmful to health).

Second, scientists tend to use a more sophisticated model or mechanism to explain things. Therefore, they could explain the fermentation mechanism of Pu’er tea, make well-informed observations about Aspergillus niger being the dominant micro-organism in Pu’er tea and its ability to inhibit and degrade aflatoxin, and clarify the conditions for the survival of aflatoxin and its other properties (such as being insoluble in water). In contrast, laypeople could resort only to superficial analogous argumentation. For example, some laypeople supporting Fang resorted to statements that the incidence of liver disease in southern China is higher than in the north because the south has higher temperature and humidity and the rice tends to grow mould (Pu’er tea is produced and consumed in the south, suggesting that the long storage time of Pu’er tea can lead to the growth of harmful substances). Other laypeople opposed Fang's view by citing that many Pu’er tea drinkers do not get cancer. They thought that was a probability question, similar to the link between smoking and cancer.

Fourth, scientists and laypeople differ in their styles of reasoning. A style of reasoning is a pattern of inferential relations that are used to select, interpret and support evidence for scientific results (Bueno, 2012). There are remarkable differences in the way scientists and laypeople defend their views and the materials they use in their arguments. Scientists tend to quote or refute experimental data, while stressing the importance of sampling methods and detection methods. In Fang's article, he cited data from three scientific papers. A scientist who opposed him admitted that, since Fang has presented data, we cannot just say whether he is right or wrong, but that the data cited by Fang is contrary to the common principles of scientific research and the sample data selected is highly unscientific. Another scientist opposing Fang said that researchers should speak with data. Experts from multiple research institutes in the country should be organized to detect aflatoxin in 10,000 samples of Pu’er tea taken from major Pu’er tea-growing regions. Scientists cited testing results produced by some agencies that supported their views and criticized the unscientific use of data in Fang's article. Some scientists noted that a sample used in one of the three scientific papers was wet-processed Pu’er tea; other scientists suggested that the testing agency in Guangzhou might have used non-conforming Pu’er tea as a sample, given the region's humid climate.

In comparison with scientists, most laypeople drew upon everyday experiences by way of argumentation with statements such as ‘People in Yunnan have drunk Pu’er tea for generations’ (suggesting that the tea is not harmful); ‘I have known no Pu’er tea drinkers in my life who got cancer’; ‘Cigarette vendors are not necessarily smokers and drug dealers are not necessarily drug users, but 99% of tea vendors are tea drinkers’ (suggesting that people who sell Pu’er tea drink it themselves and will not cheat). Some people even cited personal character to support their view with comments such as ‘Besides believing in science, I also believe in personal character, and I will not believe in anything uttered by people of a questionable character’ (referring to Fang), and ‘It is a joke for a person who never drinks Pu’er to talk about whether Pu’er tea is carcinogenic’ (Fang said in his article that he does not drink Pu’er tea).

3. Conclusion

An epistemic perspective is an important dimension in which scientists and laypeople differ concerning their thinking/cognition. Laypeople think in terms of their everyday experiences, and they are concerned about immediate issues (such as health). Generally, they can relate only to things with which they have direct experience and depend on cognitive resources (accumulated in executing everyday tasks) in a process that involves their wishes, emotions and trust. In contrast, scientists face a world of disenchantment where epistemic objects and processes are objectified. They believe that data, models and mechanisms used in scientific activities are part of objective laws and govern laypeople's experiences.

In the debate on Pu’er tea, it is observed that the differences between scientists and laypeople in their epistemic perspectives are not absolute. Scientists and laypeople may switch between or combine each other's different epistemic perspectives. For example, some lay readers also mentioned that the presence of aflatoxin alone cannot be equated with carcinogenicity because the amount involved also matters. Besides, scientists may sometimes also deviate from the objectivation requirement when discussing an issue. For example, a scientist explained why drinking Pu’er tea is not carcinogenetic in an analogical way: even bread goes mouldy after a while due to the presence of fungi in the air. Most of those fungi are not harmful, but those that are will produce aflatoxin. While the production process of Pu’er tea is likely to produce aflatoxin, the overwhelming majority of Pu’er tea sold in the market is free from the substance. Even if the substance is present, it will be harmless because the amount will be minimal, inhibited and impossible to grow significantly. Here, the scientist was drawing an analogy to everyday experiences.

The failure of communication between scientists and laypeople is to a significant extent attributable to the difference in their epistemic perspectives. In the debate on Pu’er tea, the difference is that, while scientists pay attention to aflatoxin, laypeople are concerned about health. Aflatoxin represents a health risk. Risk has its objective and subjective dimensions. It is difficult for people looking at a thing from one perspective to understand other people who look at the same thing from a different perspective. The failure of such communication is not coincidental but speaks of a perspective paradox: when scientists adhere to their trained perspective, they cannot satisfactorily answer the questions asked by laypeople. However, if they switch to laypeople's perspectives, the answers they provide may be incongruous with their role as scientists.