At the end of their critical analysis of microbiota-gut-brain (MGB) research, Hooks et al. identify the potentially negative consequences of the popularity of this research in the press and on social media. They aptly point out that the appeal of some of these studies is their continuity with what they characterize as commonsense conceptions of health. In this commentary, I will briefly describe a conception of common sense that can be used to provide an explanation for the easy absorption of MGB research into commonsense views about health and why this might be detrimental.
Commonsense conceptions tend to be characterized in contrast to scientific notion (i.e., common sense is not science, and commonsense concepts are not scientific concepts). When they are considered unscientific, commonsense notions are often described as intransigent or static, which can discourage attempts to change them. This way of characterizing common sense is wrong because it ignores the ways in which it is shaped by science. A better way of defining common sense is as continuous with science (Sellars, Reference Sellars1963). Even further, the right characterization of commonsense views is as empirically evaluable folk theories, such as folk psychology (Churchland, Reference Churchland1992) or folk morality (Gligorov Reference Gligorov2016) used in everyday life to explain and predict human behavior. As I have argued previously (Gligorov Reference Gligorov2016), folk conceptions are influenced by scientific discoveries and are in fact shaped by them in a variety of different ways. Advances in neuroscience have promoted the identification of psychological traits with brain processes and have shaped our conceptions of personal identity, privacy, free will, and even our notions of death (Gligorov Reference Gligorov2016).
Similarly, the human microbiome might shape commonsense conceptions of health and of personal identity (Gligorov et al. Reference Gligorov, Azzouni, Lackey, Zweig, Rhodes, Gligorov and Schwab2013). This might happen by characterizing individuals as superorganisms and shifting conceptions of health to include keeping a healthy microbiome. Furthermore, being a superorganism might expand moral responsibilities to include the duty to keep a healthy microbiome and prevent the spread of disease (Battin et al. Reference Battin, Francis, Jacobson and Smith2008). Incorporating facts about the human microbiome would lead to a reconceptualization of what it is to be a healthy person or what is required to lead a healthy lifestyle. For example, claims that certain bacteria will promote health might change attitudes away from preventing contamination. The rush to use probiotics is one way in which this change in attitude is manifested. MGB research would have an even more straightforward effect on views about personal identity because the claim is that changes in gut microbiota can affect psychological traits, such as anxiety or mood, which are constitutive of how we think of ourselves.
The potential shifts in common sense that might occur because of MGB research would be only the latest iteration of science shaping common sense. Consider that any of the claims cited by Hooks et al. as being part of our common sense about health and nutrition, such as eating fresh food, minimizing fat and sugar, and more exercise are all edicts based on scientific studies establishing causal connections between nutritional styles and some aspect of our health. But because most of these recommendations are learned secondhand by the public, not from scientists or scientific publications, their scientific etiology can be lost.
Circling back to the worries raised by Hooks et al., one is that MGB research is influencing everyday notions of health prematurely and promoting perhaps false beliefs about how to treat psychiatric disease, and the other is that MGB research seems to be confirming commonsense platitudes about health rather than adding to them in ways that might lead people to forego taking medication when they might need it. I would like to underscore both of these worries by using the view I just described about how MGB research can change personal identity.
If it is the case, as I argue, that commonsense notions are not only affected, but also continuously revised by scientific discoveries, then the popularization of MGB research will have an impact on common sense about health. Whether that influence is positive or negative will trail the quality of MGB research and the accuracy of the claims derived from that research. But there is one way in which early scientific mistakes could have more permanent and perhaps negative consequences on common sense. Although science is self-correcting because there are established ways in which unsupported claims can be eliminated, the path to self-correction is not as well trotted in common sense. One of the reasons for why commonsense notions about health might be particularly difficult to revise is precisely because they become incorporated into conceptions of identity. Once an individual becomes committed to being healthy in particular way, then that becomes a part of their narrative identity – it becomes part of how they tell a story of who they are (DeGrazia Reference DeGrazia2005). Additionally, whether they keep healthy and live well takes on moral dimensions and becomes action guiding; they wish to continue living the right way. This is why scientific claims that are continuous with beliefs already endorsed, say about what is natural or healthy, are much easier to reinforce than they are to revise. For example, if individuals become committed to living a natural and healthy lifestyle, which they think requires cultivating the microbial environment in their gut buy using probiotics, any study that confirms that particular way of keeping healthy will be easier to believe because it is already congruent with their established concept of health. Similarly, scientific claims challenging established views about health will take longer to become entrenched in common sense because they require changes not only to particular beliefs, but also to parts of an individual's narrative identity. Hence, beliefs about the causal connections between gut microbiota and brain health, if disproved, might be easier to revise within the relevant scientific community than they might be to eliminate from common sense.
At the end of their critical analysis of microbiota-gut-brain (MGB) research, Hooks et al. identify the potentially negative consequences of the popularity of this research in the press and on social media. They aptly point out that the appeal of some of these studies is their continuity with what they characterize as commonsense conceptions of health. In this commentary, I will briefly describe a conception of common sense that can be used to provide an explanation for the easy absorption of MGB research into commonsense views about health and why this might be detrimental.
Commonsense conceptions tend to be characterized in contrast to scientific notion (i.e., common sense is not science, and commonsense concepts are not scientific concepts). When they are considered unscientific, commonsense notions are often described as intransigent or static, which can discourage attempts to change them. This way of characterizing common sense is wrong because it ignores the ways in which it is shaped by science. A better way of defining common sense is as continuous with science (Sellars, Reference Sellars1963). Even further, the right characterization of commonsense views is as empirically evaluable folk theories, such as folk psychology (Churchland, Reference Churchland1992) or folk morality (Gligorov Reference Gligorov2016) used in everyday life to explain and predict human behavior. As I have argued previously (Gligorov Reference Gligorov2016), folk conceptions are influenced by scientific discoveries and are in fact shaped by them in a variety of different ways. Advances in neuroscience have promoted the identification of psychological traits with brain processes and have shaped our conceptions of personal identity, privacy, free will, and even our notions of death (Gligorov Reference Gligorov2016).
Similarly, the human microbiome might shape commonsense conceptions of health and of personal identity (Gligorov et al. Reference Gligorov, Azzouni, Lackey, Zweig, Rhodes, Gligorov and Schwab2013). This might happen by characterizing individuals as superorganisms and shifting conceptions of health to include keeping a healthy microbiome. Furthermore, being a superorganism might expand moral responsibilities to include the duty to keep a healthy microbiome and prevent the spread of disease (Battin et al. Reference Battin, Francis, Jacobson and Smith2008). Incorporating facts about the human microbiome would lead to a reconceptualization of what it is to be a healthy person or what is required to lead a healthy lifestyle. For example, claims that certain bacteria will promote health might change attitudes away from preventing contamination. The rush to use probiotics is one way in which this change in attitude is manifested. MGB research would have an even more straightforward effect on views about personal identity because the claim is that changes in gut microbiota can affect psychological traits, such as anxiety or mood, which are constitutive of how we think of ourselves.
The potential shifts in common sense that might occur because of MGB research would be only the latest iteration of science shaping common sense. Consider that any of the claims cited by Hooks et al. as being part of our common sense about health and nutrition, such as eating fresh food, minimizing fat and sugar, and more exercise are all edicts based on scientific studies establishing causal connections between nutritional styles and some aspect of our health. But because most of these recommendations are learned secondhand by the public, not from scientists or scientific publications, their scientific etiology can be lost.
Circling back to the worries raised by Hooks et al., one is that MGB research is influencing everyday notions of health prematurely and promoting perhaps false beliefs about how to treat psychiatric disease, and the other is that MGB research seems to be confirming commonsense platitudes about health rather than adding to them in ways that might lead people to forego taking medication when they might need it. I would like to underscore both of these worries by using the view I just described about how MGB research can change personal identity.
If it is the case, as I argue, that commonsense notions are not only affected, but also continuously revised by scientific discoveries, then the popularization of MGB research will have an impact on common sense about health. Whether that influence is positive or negative will trail the quality of MGB research and the accuracy of the claims derived from that research. But there is one way in which early scientific mistakes could have more permanent and perhaps negative consequences on common sense. Although science is self-correcting because there are established ways in which unsupported claims can be eliminated, the path to self-correction is not as well trotted in common sense. One of the reasons for why commonsense notions about health might be particularly difficult to revise is precisely because they become incorporated into conceptions of identity. Once an individual becomes committed to being healthy in particular way, then that becomes a part of their narrative identity – it becomes part of how they tell a story of who they are (DeGrazia Reference DeGrazia2005). Additionally, whether they keep healthy and live well takes on moral dimensions and becomes action guiding; they wish to continue living the right way. This is why scientific claims that are continuous with beliefs already endorsed, say about what is natural or healthy, are much easier to reinforce than they are to revise. For example, if individuals become committed to living a natural and healthy lifestyle, which they think requires cultivating the microbial environment in their gut buy using probiotics, any study that confirms that particular way of keeping healthy will be easier to believe because it is already congruent with their established concept of health. Similarly, scientific claims challenging established views about health will take longer to become entrenched in common sense because they require changes not only to particular beliefs, but also to parts of an individual's narrative identity. Hence, beliefs about the causal connections between gut microbiota and brain health, if disproved, might be easier to revise within the relevant scientific community than they might be to eliminate from common sense.