Recent “ideational” research on populism (Hawkins et al., 2019) has demonstrated that populist beliefs are widespread in national populations. These beliefs refer to shared representations of a social order based on the competitive and antagonistic relationship between two loosely defined social categories, “the people” (represented as a morally upright but victimized group), and “the elite” (represented as a deceitful and corrupt group that takes advantage of the masses) (Mudde, 2004).¶ Endorsement of populist representations has been shown to be linked with various societal and individual antecedents. At the societal level, populism has been associated with weak, unstable, and corrupt governments (Ziller & Schübel, 2015), with specific events and time periods such as economic or social crises (Hernández & Kriesi, 2016; Pappas & Kriesi, 2015), and with negative evaluations of elite performance, and more generally with dissatisfaction with democracy (Berman, 2019). Individual factors associated with the endorsement of populist attitudes include motivational drivers such as existential uncertainty (Hogg, 2021), distrust in people and in institutions (Staerklé & Green, 2018), as well as low levels of education (Arzheimer, 2009).¶ A general sense of injustice, victimization, and entitlement may underlie many of the factors that have been shown to be associated with populism. In line with this argument, studies have pointed to relative deprivation as a key driver of populism (Elchardus & Spruyt, 2016). Feelings of relative deprivation are based on (often implicit) comparisons between two parties and emerge when collective circumstances are consistently perceived as unfavorable for oneself or one's group. As a result, the perceived disadvantages are seen as unfair, especially when they are seen to reflect fundamentally unfair social arrangements that provide significant privileges to some parts of the population. Such perceptions of system-embedded injustice may fuel the idea of the existence of two antagonistic categories of people, those whom the system favors and those whom it does not. This representation of the social order based on the cleavage between the lucky few and the unlucky many may then form a fertile ground for populist ideas.¶ Studies in Western and industrialized countries have explored relative deprivation as a consequence of globalization processes and ensuing labor market changes and have labeled those individuals who feel relatively deprived and attracted to populism as the “losers of globalization” (Kriesi et al., 2008; Norris & Inglehart, 2019). In a rapidly changing world with radically new sources of information and communication technologies, people can be more easily aware of their situation and opportunities relative to those of others. Regardless of whether comparative evaluations are true or not, they make structurally disadvantaged (that is, unemployed, underemployed, low-skilled, low-educated, and precarious) individuals believe that they are left behind, and that they are entitled to more than what they have. Relatively deprived individuals would therefore be particularly sensitive to populist arguments that both vilify elites and glorify the “forgotten” people.¶ Variants and Subdimensions of Populism: Antielitism and People Sovereignty¶ Populism is a heterogeneous political phenomenon both in terms of its multiple belief dimensions and its concrete manifestations. On one hand, prior research has evidenced the multidimensional structure of populist beliefs, organized as distinct subdimensions involving attitudes towards the elite (e.g., antielitism, elite distance) and the people (e.g., people sovereignty, people homogeneity) (Akkerman et al., 2014; Rooduijn, 2014; Schulz et al., 2018; Spruyt et al., 2016). On the other hand, as a thin ideology, populism is generally associated with broader host ideologies that connect its core claims to concrete sociopolitical issues and shape individuals' political preferences (Loew & Faas, 2019).¶ Regarding its multidimensional structure, research so far has not examined the specific relationships between populist subdimensions, crisis-related science skepticism, and crisis-mitigation attitudes. In the present research, we heed calls for a more refined approach to measurement of populism (Rooduijn, 2019) by differentiating two fundamental dimensions, one related to negative judgments of elites (“antielitism”), the other to decision sovereignty of the people (“people sovereignty”). These subdimensions emphasize respectively within- and between-group dynamics of populism: People sovereignty emphasizes the intrinsic moral and political credentials of the ingroup and asks for decision-making power legitimized by the “simple, naturalistic, and reliable epistemology of ordinary people” (Mede & Schäfer, 2020, p. 481). Antielitism, in turn, refers to negative and often hostile attitudes toward various types of elites, including epistemic and scientific elites. Since populism is based on a moral antagonism between the people and the elites, these two subdimensions are likely to be related to each other, but in our study, we examine (1) whether relative deprivation is equally associated with them, and (2) whether they play specific roles in accounting for crisis-related science skepticism, and subsequently for crisis-mitigation attitudes.¶ The association with broader host ideologies is revealed by the left- or right-wing orientation of a given variant of populism. Left-wing populism conceives “the people” mostly in socioeconomic terms, claims their rights as a sovereign entity, and condemns the abuses of the elites towards them. The right-wing variant sees the people mostly in ethnonational terms, advocates the preservation of national culture and identity, and targets those groups that are seen as eroding these (Abts & Rummens, 2007). While both focus on the people and blame the ruling elites for the misfortunes that come their way, they differ in what they consider a misfortune for the people and the groups that are responsible for them.¶ Mudde and Rovira Kaltwasser (2017) distinguished between exclusionary (right-wing) and inclusionary (left-wing) populism, based on the degree of inclusiveness of its material, political, and symbolic dimensions. Differences between these two types thus depend on which groups are included in the “people” and in the “elite.” Exclusionary populism tends to define the people in ethnonational terms, thereby othering immigrants and members of the elite who are seen as “globalized” and distanced from national culture. Inclusionary populism, in turn, puts greater emphasis on social equality and associates the people with the socioeconomic underdog (Mudde & Rovira Kaltwasser, 2017). In a recent taxonomy, Zulianello (2020) adds valence populism as a third category representing a “pure” form of populism that does not interact with other ideological elements.¶ With respect to relative deprivation, political elites represent an outgroup target easy to blame for one's misfortunes. To the extent that members of political elites are thought to be advantaged in the existing social order, their actions—or lack thereof—are seen as selfishly contributing to and perpetuating the inequality between the advantaged and the disadvantaged. We therefore expect relative deprivation to be related to the antielitist subdimension of populism.¶ Relative deprivation may also affect the way individuals think about the “people.” In populist discourse, the “people” is portrayed as a victimized social category suffering the detrimental impacts of self-interested elite misbehavior. To redress this inequality, populist discourse urges the “people” to take matters into their own hands and make political decisions that are favorable for them. As a result, the “people” becomes a positively valued political identity. Hence, we expect relative deprivation to be associated with the subdimension of people sovereignty of populism.¶ Populism, Common Sense, and Science Skepticism¶ As exemplified by countless science-hostile declarations by populist leaders, skeptical attitudes towards science are a key component of populist discourse. Indeed, widespread science skepticism—understood as the systematic and unwarranted rejection of scientific knowledge and its forms of production—has gained traction over the last decade to become a defining feature of contemporary zeitgeist (Rutjens et al., 2021).¶ Science skepticism has been explained in terms of an experiential discrepancy between individuals' own concrete experiences and more distant forms of knowledge that cannot be verified firsthand (Mede & Schäfer, 2020). The COVID-19 pandemic has strengthened this perceptual divergence as dire media accounts of pandemic hotspots were often inconsistent with people's own experiences in (largely rural) places without a large number of infections. As a result, many citizens may have thought that the crisis was overblown and that measures of containment such as movement restrictions and lockdowns were excessive (Brubaker, 2021).¶ But more research is needed to reach a better understanding of the psychological factors underlying science skepticism. We argue that science skepticism is likely to run deeper than experiential discrepancy and may in fact reflect a fundamental epistemological cleavage between lay and expert forms of knowledge. Indeed, in populist discourse, concrete, immediate and familiar everyday thinking—“common sense”—is portrayed as a form of knowledge that is equal to, if not superior, to expert and scientific knowledge (Imhoff et al., 2018).¶ Variations of such a cleavage between everyday and scientific knowledge have been described in various disciplines. In modern anthropology, Lévi-Strauss (1962) compared the “savage” to the “scientific” mind, and in social psychology, Moscovici (1961) opposed “novice” to “expert” thinking, the former being a key feature of social representations (Moscovici & Hewstone, 1983). While these various conceptualizations differ in their analysis of the nature of this epistemological discrepancy, they concur that everyday thought follows its own logic, is qualitatively different from scientific thought, and should therefore not be considered an impoverished or biased form of higher-order thinking (see Wagner & Hayes, 2005, for an overview). Everyday thinking is shaped by pragmatic concerns of ordinary social life, is based on relative consensus within a social collective, and develops out of the necessity to communicate meaningfully with others (Moscovici & Hewstone, 1983). In contrast to scientific thought, it signals belongingness to social groups and has therefore an important identity-generating function: We are what we believe.¶ In recent years, the antagonism between lay and scientific thinking has become increasingly politicized. Common sense—as a legitimized and emancipated form of knowledge of its own—is now mobilized as a political argument against elites. Commonsense thinking has become associated with “ordinary people” whereas scientific thinking has become associated with despised elites. In other words, common sense has become a political weapon in itself against purported elite and scientific dominance. This view suggests that the “people” are different from experts in a deeply psychological sense, namely that they think differently, and that their everyday mode of thinking is, in fact, as valid or even more valid than the cold and complicated logic of scientific and expert thinking (Mede & Schäfer, 2020). This “epistemological populism” is based on assumptions according to which firsthand experience might sometimes be the more trustworthy form of knowledge and considers common sense to be virtuous and legitimate because it rests on authentic and unmediated everyday experience (Saurette & Gunster, 2011).¶ Distrust in science is expressed across various domains, including climate change denial (Huber, 2020), pandemic containment policies, vaccine hesitancy and refusal (Stecula & Pickup, 2021), and the rejection of evolution as a basic principle of the development of life on earth (see Rutjens, Heine, et al., 2018; Rutjens, Sutton, et al., 2018). This dimensionality is important for our analysis of the effects of politicization of the lay knowledge-science discrepancy. In the present research, we focus on skepticism towards scientists and expert knowledge on two specific global topics: climate change and the COVID-19 pandemic. This choice of a narrower approach to science skepticism implies that our results can hardly be generalized to science skepticism in general, but it has the distinct advantage of closely reflecting the crisis-related political debate of recent years, thereby providing the opportunity to examine the relationship between variants of populism and science attitudes. Indeed, an important cleavage in the populist family in their reactions to both climate change and the COVID-19 pandemic has been observed, especially in Europe (Stavrakakis & Katsambekis, 2020). This study allows us to examine the ways in which the lay populist mentality predicts crisis-related skepticism in contexts where populist actors accept the “science” behind climate change and the COVID-19 pandemics.¶ We expect crisis-related science skepticism to be associated with both antielitism and people sovereignty as subdimensions of populism, but for different reasons. Scientific knowledge is incarnated by scientists (e.g., professors, researchers, academics) who can be cast as members of the “elite” by populists. Hence, negative attitudes towards elites should imply negative attitudes towards scientists and scientific institutions and therefore increase skepticism towards knowledge produced by these elite members. In this view, science skepticism would be mostly based on distrustful attitudes towards the producers of scientific knowledge rather than on the intrinsic superiority of populist epistemology. A positive relationship between people sovereignty and crisis-related science skepticism, in turn, would suggest that the “will of the people” and the request for popular sovereignty is legitimized with the purported superiority of the certain, practice-oriented, and straightforward “wisdom” of ordinary people, as opposed to abstract, out-of-touch, and uncertain scientific knowledge.¶ Science Skepticism and Crisis-Mitigation Attitudes¶ The main goal of our study is to provide a comprehensive model that explains how populist attitudes and crisis-related science skepticism are related to attitudes towards mitigation measures of global crises. We examine two outcome variables that refer to internal versus external dimensions of global crisis mitigation, namely a sense of personal responsibility (and thus an internal motivation) to fight climate change, and an attitude towards external governmental measures destined to contain the spread of the COVID-19 pandemic. This choice allows us to cover a broad spectrum of possible reactions to global crises, as both the individual and the collective level are mobilized.¶ We therefore expect crisis-related science skepticism, as a form of politicized commonsense knowledge, to be associated with a lower sense of personal responsibility to reduce climate change, and with greater opposition to a governmental measure to contain the COVID-19 pandemic. We further hypothesize that such science skepticism mediates the relationship between the two populist subdimensions (antielitism and people sovereignty) and crisis-mitigation attitudes, but it does not exclude the possibility of a direct link between both populist subdimensions and crisis-mitigation attitudes.¶ To sum up, we test a model in which relative deprivation should lead to antielitism and people sovereignty. These populist subdimensions are in turn expected to be associated with crisis-related science skepticism, which then should predict lower personal responsibility for climate change mitigation and greater opposition to a governmental COVID-19 containment policy. We leave open the possibility of a direct link between populist subdimensions and crisis-mitigation measures, without the mediating role of science skepticism (see Figure 1, Panel 1).