Abstract
Moral conviction reflects an absolute stance about an issue and is linked to both conventional and radical action. We suggest that moral conviction can arise from ascribing intrinsic value to the environment (Study 1) and non-human animals (Study 2) and, therefore, affect conventional and radical action – but the latter primarily where there is consensus about the sharedness of those values. Two experiments (N = 238, 166) examined effects of intrinsic value framing, and presence/absence of value consensus, on moral conviction, and commitment to conventional or radical action. In Study 1, an intrinsic (vs. extrinsic) value frame increased moral conviction which predicted conventional and radical action, irrespective of consensus. In Study 2, moral conviction predicted radical and – unexpectedly – conventional action only when consensus was present. The findings provide new insights into when people take radical and conventional action to protect animals and the environment, and into what can intensify moral conviction.
Keywords
Introduction
. . . humans are natural storytellers, and use narrative to influence others. . . . It would be a mistake as scientists – and as politically and socially engaged citizens – to dismiss the importance of this reflective process in shaping our morality and, consequently, the world in which we live. (Bloom, 2010, p. 490)
The last few years have provided numerous examples of people engaging in both conventional actions to promote justice for the environment and non-human animals, as well as more radical actions. In October 2022, climate protesters threw soup over Vincent van Gogh’s Sunflowers painting at the National Gallery in London and then glued themselves to the wall to protest fossil fuel production in the UK. Nine days later, members of a German environmental group threw mashed potatoes over a painting by Claude Monet. Elsewhere, hundreds of thousands of people across the world have engaged in conventional forms of action to protest climate inaction via participating in climate strikes. In this paper we adopt the distinction between conventional actions (those that are legal, relatively commonplace, accepted) and radical actions (those that illegal, more extreme, less widely accepted; Louis et al., 2020). Given that both forms of action may play a role in advocating for concerted action to address the climate crisis and other environmental challenges (Lizzio-Wilson et al., 2022; Shuman et al., 2024; Simpson et al., 2022; Uluğ & Acar, 2018), understanding the motives of people who engage in conventional and radical actions is of utmost societal importance.
The existing evidence suggests that both conventional and radical forms of action flow from fundamental beliefs about right and wrong. For instance, moral conviction – defined as a strong, absolute stance about fundamental right or wrong – has been shown to predict engagement in conventional forms of action (e.g., Agostini & van Zomeren, 2021; Morgan et al., 2010; Skitka & Bauman, 2008). Yet, there is also evidence that moral conviction can propel people towards radicalism (e.g., Mooijman et al., 2018; Mullen & Nadler, 2008; Pauls et al., 2022; Reifen Tagar et al., 2014). Skitka and Mullen (2002) suggested that, whilst moral convictions can be associated with action to advance the rights and protections for disadvantaged groups, it can also have a “dark side” whereby people may dismiss procedural fairness, overlook normative safeguards, or even justify harmful means when they perceive the issue as morally non-negotiable. Despite the obvious real-world relevance of moral conviction and action, little research considered the role of moral conviction and its association with commitment to both conventional and radical forms of action (but see Pauls et al., 2022; Zaal et al., 2011).
In this paper, we investigate two specific gaps in this literature. First, although there is evidence that moral conviction may be related to both conventional and radical forms of action, it is less clear what the sources of that moralized stance are. What are the drivers of moral conviction? Skitka et al. (2021) provided evidence that emotions like disgust play an important role in the foundation of moral conviction. In this paper we take a different tack to suggest that variation in moral conviction can also be explained by different types of values that people ascribe to non-human animals and the natural environment (see also van Zomeren at al., 2024) Specifically, we test whether framing (Chong & Druckman, 2007) the environment (Study 1) and non-human animals (Study 2) as intrinsically valuable, strengthens moral conviction compared to an extrinsic value frame (Study 1) and over time (Study 2).
Second, we suggest that whilst having a strong moralized stance on an issue will be sufficient to promote engagement in conventional action, it will not be sufficient to promote radical action. Linking with Bloom’s (2010, above) observations, to be committed to engage in more radical action, we propose that people need to perceive that their position is shared by others (i.e., there must be consensus about their worldviews; Mooijman et al., 2018). Thus, whilst moral conviction can indeed be associated with conventional and radical forms of action, it is likely that the relationship with radical action primarily exists when there is also the perception that others share one’s position (i.e., consensus, e.g., Bicchieri & Mercier, 2014; Krueger, 1998; Prentice & Paluck, 2020). This paper tests these two propositions in the context of conventional and radical actions to oppose mining for fossil fuels in Australia (Study 1) and support for animal welfare (Study 2).
The Role of Intrinsic Versus Extrinsic Values in Shaping Moral Conviction and (Conventional and Radical) Collective Action
Although it is recognized that moral convictions play an important role in shaping collective action (Agostini & van Zomeren, 2021), relatively little research has considered the factors that may strengthen or intensify moral conviction. Indeed, Skitka has been reported as calling this “the million dollar question in this area of research” (see Täuber et al., 2015, p. 460). Here we focus on framing the environment or non-human animals as intrinsically valuable as a predictor of moral conviction. In this context, framing refers to how information is presented in ways that highlight either intrinsic or extrinsic value, thus shaping how participants interpret the significance of the environment or non-human animals (see Chong & Druckman, 2007). We propose that how a particular issue is framed in terms of the value that is ascribed to the entity (the environment, non-human animals), will influence the degree of moral conviction and subsequent commitment to (conventional and radical) collective action.
Linking Intrinsic (vs. Extrinsic) Values to Moral Conviction
Valuing relates to how we assign value to things, objects or beings at an abstract and/or concrete level (Maio, 2010). There is a large inter-disciplinary literature on values, which are understood to be of critical importance for efforts to preserve and defend the environment, including non-human animals, because of their broad influence on attitudes, motivation and behaviors (e.g., Maio, 2010; Olson & Zanna, 1993; Schwartz, 2014; see Hurst et al., 2013 for a meta-analysis). Several traditions of values research highlight the distinction between valuing the environment for its own inherent qualities as opposed to the utility that it offers for humans (see Ahn & Reeve, 2021; Dietz et al., 2005). For instance, Manfredo et al. (2016, 2020) distinguish between domination values which suggest the environment should be used to benefit humans, whilst mutualism values view wildlife and the natural environment as part of one’s extended network. Elsewhere, the distinction between ecocentrism and anthropocentrism suggests that people can afford moral consideration to the environment and non-human animals because nature is understood to have intrinsic value (ecocentrism) or because of its effects on humans (anthropocentrism; see Kortenkamp & Moore, 2001; Thompson & Barton, 1994).
In this paper we draw from moral philosophy to examine this distinction through the lens of intrinsic and extrinsic values (Rønnow-Rasmussen, 2015; Vilkka, 2021; Zimmerman, 2001). Intrinsic values implies that the thing, object or being is valuable in and of itself, independent of its utility and for its own sake, while extrinsic values are those where the thing, object or being is valued because of its usefulness in attaining other goals or avoiding other costs (Zimmerman, 2001). In the context of environmental and non-human animals, intrinsic values suggest that these have value in their own right whereas extrinsic values suggest that these are valued because of their contribution to some other goal or purpose for humans. For example, people may be opposed to the development of a new mine because of the degradation of nature and culturally significant sites (intrinsic value) and/or be opposed because a mine would affect tourism to the area (extrinsic value). Bastian et al. (2023) applied this distinction to understand attitudes towards nature, revealing that intrinsically valued “sacred” entities tend to be afforded greater moral significance. Building on this reasoning, we suggest that because intrinsic and extrinsic value frames attribute value differently, these may have consequences for moral conviction (see also Maio, 2010).
It is important to be clear at the outset about the conceptual distinction between values and moral conviction. Here, intrinsic value concerns what is valued about the environment or non-human animals (Zimmerman, 2001), while moral conviction is a meta-cognitive evaluation about the quality of one’s attitude as reflecting an objective moral absolute (or not; Skitka et al., 2005). We test the proposition that, because an intrinsic form of valuing presents the object as non-negotiable and important in its own right, it may provide a basis for moralization. An intrinsic value frame emphasizes the inherent worth of the object or being, independent of external or secondary considerations. Because intrinsic valuing frames the object as inherently worth protecting, it may prompt a shift from valuing something for its own sake to believing that one ought to hold this stance, thereby strengthening moral conviction (Skitka et al., 2005). Thus, we propose that an intrinsic value frame of the inherent importance of the natural environment (Study 1) and non-human animals (Study 2) is likely to be a strong driver of moral conviction because it encourages this metacognitive shift.
Effects of Intrinsic and Extrinsic Values on Conventional/Radical Action
If framing the environment or non-human animals in terms of intrinsic value is more likely to promote moral conviction, what are the consequences for behaviors to protect the environment using conventional tactics (e.g., protest in climate strikes) and/or radical tactics (e.g., vandalism, direct actions)? While there is strong meta-analytic evidence that moral conviction is associated with conventional (Agostini & van Zomeren, 2021) and more radical forms of action (Pauls et al., 2022), only a few studies have linked intrinsically valued entities being harmed, with willingness to engage in conventional/radical action.
The impact of intrinsic values on support for extreme action was shown in a series of field experiments conducted in the violent Israeli-Palestinian conflict, where contested issues involved the morality of the group’s action strategies (Ginges et al., 2007). Specifically, Ginges et al. (2007) found that adding material incentives to negotiation deals (such as offering money to compromise “holy” land; ostensibly extrinsic values) increased anger and disgust, yielding greater support for violent opposition. These findings have been replicated in various real-world contexts, and together they strongly suggest that when a dispute is about intrinsic or “sacred” issues, people will be more likely to support the use of extreme forms of action (Dehghani et al., 2009; Ginges & Atran, 2009, 2013; Ginges et al., 2011). However, these studies did not include a measure of conventional action.
There is also evidence that framing an issue in terms of intrinsic value can be associated with conventional action. Leidner et al. (2018) showed that arguments against torture of humans (i.e., sentient objects) increased demand for restoring the injustice of torture (conventional action) compared to framing the issue in extrinsic terms. However, this research did not include a measure of radical action.
Thus, overall, the existing research shows the effect of intrinsic or extrinsic value frames on the different types of collective action separately, but it leaves unanswered what the effects would be when conventional and radical actions are considered together. We address this gap in Study 1 by experimentally invoking intrinsic or extrinsic frames and investigating the impact on both conventional and radical collective action through moral conviction.
The Role of Consensus in Shaping Moral Conviction and (Conventional and Radical) Collective Action
Alongside the observation that people can ascribe value differently (i.e., things can be valued for intrinsic or extrinsic reasons), there are also differences in how particular groups or segments of society share values (e.g., Schwartz & Sagie, 2000). While social consensus refers to the idea that “the thoughts, feelings, and actions of others are similar to one’s own” (e.g., Krueger, 1998), value consensus refers to an agreement or shared understanding between two people (Wenzel et al., 2021) or within a particular group (Schwartz & Sagie, 2000) about the values that define them relative to other groups (van Zomeren et al., 2024). We test the proposition that consensus may impact the downstream effects of value framing on moral conviction and radical action specifically.
Specifically, we speculate that the links between an intrinsic value frame and moral conviction will be stronger when the intrinsic value frame is understood to be shared and consensually held. Although the literature on moral convictions suggests that it is an intra-individual meta-cognition (Skitka et al., 2005), others suggest that moral positions are not arrived at alone, solely through internal reasoning, but are actively socially influenced (see Bloom, 2010, above; Carnes et al., 2015; Ellemers & van den Bos, 2012). That is, moral worldviews are also influenced by the perceived positions of other people (see Bicchieri & Mercier, 2014; d’Amore et al., 2022; Lindström et al., 2018; Monroe et al., 2018). Where consensus is present – and one’s values are understood to be shared with important others – this may act to further validate one’s worldviews, making values seem more objective, “real”, and resistant to change (Hardin & Higgins, 1996). Worldviews that are seen as more objectively true and absolute are key features of moralization (Skitka et al., 2005). Thus, we extend our analysis of intrinsic and extrinsic value frames to also explore the effects of consensus about those values, on moral conviction.
An understanding of the role of consensus may help to solve a second challenge: there is some extant evidence that moral conviction by itself may not be sufficient to promote more radical forms of action. Specifically, in an analysis of Twitter data and in a series of experiments, Mooijman et al. (2018) demonstrated that moral conviction is not always sufficient for engagement in radical actions. Rather, Mooijman et al. (2018) presented evidence that believing that important other people share their worldviews (i.e., consensus) was necessary to realize the effects of moral conviction on participation in more extreme (violent) forms of action. We are not aware of other tests of the potentially moderating effects of consensus on moral convictions and (conventional/radical) collective action and, thus, our hypotheses are guided primarily by the evidence presented by Mooijman et al. Accordingly, we suggest that when individuals perceive that like-minded others share one’s views about the intrinsic value of non-human animals and the natural environment (i.e., there is a consensus; moderator variable), these conditions will crystallize (increase) the strength of the relationships between intrinsic value framing (versus extrinsic value framing; independent variable), moral conviction (mediator variable) and radical action (dependent variable). Put differently, framing an issue in terms of intrinsic values will be associated with commitment to radical action via moral conviction primarily when consensus about intrinsic values is perceived between like-minded others.
In contrast, we expected that a preference for conventional action would be associated with moral conviction irrespective of the absence or presence of consensus. Indeed, in many studies moral conviction has been shown to be associated with conventional collective action (Agostini & van Zomeren, 2021; Morgan et al., 2010; Skitka & Bauman, 2008). This is because, adhering to accepted, common and legal routes for conventional action carries less risk compared to more radical forms of action (Cross & Snow, 2012). Thus, framing non-human animals and natural environments as having intrinsic value are necessary for both conventional and radical action because of its association with moral conviction, but it is not sufficient for radical action, where a consensus is also required (Mooijman et al., 2018).
Where do perceptions of consensus (agreement, similarity) come from? Consensus is not a passive or static reflection of values but is shaped through social influence (Turner, 1991) and is often inferred from the social context, including through things that people say to one another (Postmes et al., 2005). Indeed, in Mooijman et al.’s (2018) research, consensus was communicated through the social interactions of people on social media. Here, we manipulate consensus via exposure to an interactive discussion between a small group of individuals (i.e., participants watched a small group interaction in which other supporters expressed consensus about a shared intrinsic/extrinsic value; see also Mackie & Cooper, 1984).
Overview of Studies
We introduced this paper with examples of people engaging in “real world” action to protect the environment and animals within it. There is growing interest in how psychological research can help explain these behaviors and inform efforts to strengthen public commitment to environmental and non-human animal protection (e.g., Barth et al., 2021). The present research extends this literature by experimentally investigating the impact of intrinsic value (vs. extrinsic) framing on commitment to radical and conventional forms of collective action, via moral conviction and under conditions where consensus about those values was present or absent. We test whether the relationship between intrinsic versus extrinsic values and moral conviction, as well as the relationship between moral conviction and commitment to radical action, would be moderated when participants watched a small group interaction in which other people shared their values and reached agreement about them, that is, consensus (versus a passive control).
Study 1 investigated these relationships in the context of justice for the environment. In Study 2, we investigated whether moral conviction involving justice for non-human animals in factory farms increases as a function of intrinsic consensus and whether increased moral conviction increases commitment to conventional and radical collective action.
Transparency and Openness
Two studies are presented here which were not pre-registered. We report how we determined sample size and a sensitivity analysis for each study. We also report data exclusions (if any), inclusion/exclusion criteria and whether inclusion/exclusion criteria were established prior to data analysis. We note that we also conducted an additional preliminary study with a similar design and research context to Study 1. It is presented in the Supplemental File because it has a low sample size and does not contain a measure of moral conviction nevertheless, its pattern of effects are cognate with those reported here. We also report in the Supplemental File, effects on a behavioral measure (donation allocation) and the control condition for Study 1, both of which fell outside the central scope of the primary research questions. The study materials and measures, along with datasets, can be found at OSF link: https://osf.io/2yhdt/?view_only=71fc46f7a6534565aef4c84479d2e798.
Study 1
In Study 1, we manipulated value frame (intrinsic vs. extrinsic) and consensus (present vs. absent) and investigated their effects on moral conviction and intention to engage in conventional or radical action. The research context was opposition to Adani’s Carmichael coal mine in Queensland, Australia. The Carmichael mine and rail line have been built without consent of the Wangan and Jagalingou traditional owners of the land (Smee, 2020). Furthermore, reports have revealed that the mine will deplete water resources, damage the Great Barrier Reef, and increase global warming (Loftus, 2021). Accordingly, many Australians are opposed to the coal mine. The issue is complex but can be understood as an issue of intrinsic values relating to protection of the unique natural environment; and/or extrinsic value relating to expected loss of tourism and economic impacts on the region
Relative to an extrinsic value frame, we predicted that being exposed to an intrinsic-value frame would lead to greater moral conviction, especially when intrinsic values were socially shared (i.e., in the intrinsic consensus condition; Hypothesis 1). We predicted that moral conviction would be associated with commitment to conventional action regardless of the availability of consensus because knowledge about consensus is less essential when people follow more widely accepted, legal routes for political participation (Hypothesis 2). Finally, we expected that moral conviction would predict willingness to engage in radical action primarily when consensus about intrinsic values was present (i.e., moderated mediation; following Mooijman et al., 2018; Hypothesis 3). Overall, we expected a reliable indirect effect of intrinsic value frame on radical action via moral conviction when consensus was present.
Method
Participants and Design
An Australian community sample (N = 583) was recruited through Survey Sampling International (SSI), a digital research data provider. Participants were reimbursed with AUD$5 arranged by SSI in exchange for participation. Informed consent was obtained. Participants were excluded prior to analysis if they: did not complete (n = 182), completed very rapidly (<364 s, n = 4), took an excessive time to compete the survey (>1 hr, n = 27), agreed they had not completed the survey seriously (n = 13), and failed 2 or more attention check items (n = 58). These exclusions left a final sample of N = 299 (148 female, 150 male and 1 neither male nor female). All participants were Australian citizens or permanent residents, aged 18 to 80 (M = 48.97, SD = 15.91).
The study employed a 2 (value frame: intrinsic vs. extrinsic) × 2 (consensus: present vs. absent) between-groups factorial design. In the consensus-absent condition, participants did not view an interactive discussion about mining. We also included a baseline control condition (without any manipulations, n = 61) which was excluded from the analyses below because value frame was not included (results are presented in the Supplemental Materials for transparency). With a sample size of 238 participants, a regression analysis with 3 predictors (value frame, consensus, moral conviction), alpha = .05, and power = .80, would have a sensitivity of detecting a minimal explained variance effect size of f2 = .05, a small effect size (Faul et al., 2007). Participants accessed the questionnaire online by clicking a link on the SSI website and were randomly allocated to one of the five conditions.
Procedure
Participants were presented with one of two online news articles involving opposing plans for the Adani Carmichael coal mine Northern Queensland, Australia. These articles contained the manipulation of value frame. In the condition with exposure to intrinsic values, the prospect of mining in the region was said to present a ethical/principled challenge by threatening sacred heritage sites and biodiversity. In the condition with exposure to extrinsic values, the prospect of mining in the region was said to present an economic challenge by threatening the tourism and agricultural industries.
After reading the articles, participants in the consensus conditions watched one of two 4-minute video recordings relating to the article they had just read. Each featured a group of four volunteers (2 female; 2 male) discussing the issues raised in the articles and reaching consensus about the values involved. In the absent-consensus condition, participants were instead asked to summarize the key issues raised by the article. The passive control removes time and rumination/reflection as confounds but leaves value consensus free to vary. We nevertheless selected this approach because we were concerned that an alternative (e.g., a video in which people ostensibly disagreed on the values) would introduce other confounds. After completing the questionnaire, participants were debriefed.
Measures
All items were measured on a seven-point Likert scale (1 = Strongly Disagree; 7 = Strongly Agree), unless otherwise indicated. There were other variables beyond those reported here, including a measure of social identification with both the underlying opinion-based group and those in the interacting video.
Value Frame Manipulation Check
Five items adapted from Hanselmann and Tanner (2008) measured the extent to which the issue was seen to involve intrinsic values.
For example, “The issue of Adani’s coal mines is about something which we should not sacrifice, no matter what the benefits (money or something else)”, α = .75.
Value Frame Comprehension Check
To assess comprehension of the value framing manipulation, participants were asked what the spokesperson in the news article claimed about the Adani mine. Responses were selected from three options beginning with “This is an issue that we should . . .”: act on because of the sacred and environmental value of the region (coded as 1), act on because of the economic value of the region (coded as 2), or not act on at all (coded as 3).
Perceived Consensus Comprehension Check
Perceived consensus amongst the people interacting in the consensus conditions was assessed with: “People in the recording reached an agreement on the issues discussed” and “There was a lot of disagreement between group members on this issue” (reversed coded), r = .38, p < .001.
Moral Conviction
Four items adapted from Skitka and Morgan (2014) assessed the degree to which participants’ views about the Carmichael mine were held as a moral conviction. The items were measured on a seven-point Likert scale (1 = not at all; 7 = absolutely). For example, “Please indicate the extent to which your attitude on Adani’s Carmichael mine is based on moral principles”, α = .93. To ensure that moral conviction was empirically distinct from intrinsic/extrinsic values, we conducted a Principal Components Analysis (PCA). The analysis supported distinct factors, consistent with the theorizing that moral conviction, intrinsic and extrinsic values are distinct constructs (See Supplemental Materials for full PCA details)
Conventional Action Intentions
Seven items assessed willingness to engage in conventional actions, α = .95. For example, “I intend to sign a petition that opposes the Adani Carmichael mine”.
Radical Action Intentions
Eight items assessed willingness to engage in radical actions, α = .95. For example, “I intend to chain myself to mining machinery/equipment to oppose the Carmichael mine”.
Results and Discussion
Manipulation and Comprehension Checks
There was a significant effect of value frame manipulation, F(1, 234) = 5.75, p = .017, ηp2 = .02, such that people exposed to the intrinsic frame endorsed the intrinsic (sacred) environmental value more strongly (M = 4.89, SD = 1.04) than those in the extrinsic condition (M = 4.50, SD = 1.09). However, the effect was qualified by an unexpected interaction between value frame and consensus F(1, 234) = 4.51, p = .035, ηp2 = .019. Simple effects showed no significant differences between the consensus conditions within the context of an intrinsic value frame F(1, 234) = 0.04, p = .858. However, the interaction was driven by differences in means within the extrinsic condition, F(1, 234) = 0.63, p < .001, such that endorsement of intrinsic value was higher (M = 5.02, SD = 1.02) when social consensus was present compared to when it was absent (M = 4.39, SD = 1.03). There were no differences between consensus conditions, F(1, 234) = 0.03, p = .871, ηp2 = .00. As such, we concluded that the intended manipulation of intrinsic value framing successfully induced a greater intrinsic value of the environment than participants exposed to the extrinsic frame, but that this was also affected by the presentation of an extrinsic consensus.
For the value frame comprehension check, a 2 value frame (intrinsic vs. extrinsic) × 2 consensus (present vs. absent) ANOVA revealed a significant main effect of value frame, F(2, 234) = 108.26, p < .001, ηp² = .32. Participants in the intrinsic condition more strongly endorsed environmental value (M = 1.11, SD = 0.38), whereas those in the extrinsic condition more strongly endorsed economic value (M = 1.72, SD = 0.50). No main effect of consensus or interaction was observed (ps > .108). The consensus comprehension check showed a successful effect as the mean for perceived agreement among the people in the group discussion was significantly above the scale midpoint (4) (M = 5.62, SD = 1.13), t(139) = 16.96, p < .001, 95% CI [1.43, 1.81], d = 1.43. Sensitivity analyses to explore whether social identification conditioned the manipulations were conducted; results were unchanged when identification was included as a moderator or when low-identifiers were excluded. Full details are provided in the Supplemental Materials.
Correlations and Descriptive Statistics
The scale inter-correlations and descriptive statistics for all dependent variables are shown in Tables 1 and 2. The significant positive correlations in Table 1 provided preliminary evidence for the expected pattern of results; moral conviction was positively correlated with conventional and radical action intentions. Table 2 shows no direct effects of values frame / consensus conditions on conventional and radical action intention.
Correlations Between Dependent Variables (Study 1).
Note. N = 238.
p < .001.
Means and Standard Deviations for Dependent Variables Across Conditions (Study 1).
Note. N = 238.
Different superscripts in the rows indicate a significant difference, p < .05.
Path Analyses
We conducted a multi-group Structural Equation Model (SEM; using AMOS27 with 300 bootstraps) with consensus as the multi-group variable (moderator). Multi-group SEMs test whether specific paths are the same (or different) in different groups, which is akin to testing moderation within a SEM framework (Byrne, 2013). According to Kline (1998), a good model fit involves a non-significant chi-square, a CFI ≥.95, a RMSEA ≤.08. We tested a model in which the manipulation of value frame would predict collective action intentions through moral conviction (mediator).
We first tested a model with all paths free to vary. The model fit was excellent, χ2(4) = 1.92, p = .751, CFI = 1.00, RMSEA = 0.000, AIC = 49.92. We compared the unconstrained model with a model in which the paths were constrained to be equal, χ2(7) = 6.43, p = .490, CFI = 1.00, RMSEA = 0.000, AIC = 48.43. The difference between the models was not significant, Δχ2(3) = 4.52, p = .211. We tested whether fit improved compared to the constrained model by setting each pathway separately free, but none of the paths could be released (all ps > .05), which may suggest that the predicted mediated moderation effects were not significant. Accordingly, the constrained model was retained as the best fitting model.
Figure 1 shows the standardized regression weights. Although the tests of the overall interactions suggested no differences between the consensus conditions (see above), there is nevertheless a difference between the conditions in the path from value frame to moral conviction (one is significant, the other is not; Figure 1) and the indirect effects also differ reliably (Table 3). Specifically, Figure 1 shows that consistent with Hypothesis 1, relative to an extrinsic frame, an intrinsic frame increased moral conviction when consensus was present. Moral conviction predicted conventional action irrespective of consensus, supporting Hypothesis 2. However, intriguingly, the tests of the indirect effect revealed that an intrinsic value frame affected conventional action via moral conviction only when consensus was present (top rows of Table 3) and not when it was absent (bottom rows of Table 3). Similarly, and partially consistent with Hypothesis 3, the indirect effect of intrinsic value framing on radical intent via moral conviction was significant when consensus was present but not absent (Table 3), even though the direct path from moral conviction to radicalism did not differ reliably. Thus, when consensus was present, all indirect effects were significant (Table 3). In contrast, when consensus was absent, the indirect effects were not significant – a pattern of effects that is consistent also with the other preliminary study (see Supplemental Materials).
Path model of consensus moderating the effect of values on moral conviction as well as the effects of moral conviction on conventional and radical action intention (Study 1).
Tests of Indirect Effects (Study 1).
Note. IE = indirect effect; SE = standard error.
In sum, compared to an extrinsic frame, intrinsic values bolstered moral conviction to oppose mining and, in turn, radical action when those values are perceived to be shared amongst others. Contrary to the hypothesis that consensus would matter especially for radical action (following Mooijman et al., 2018), the indirect effects suggested that consensus matters for both conventional and radical action, while the tests of moderation within the SEM framework did not reliably differ between the two. Moral conviction predicted both conventional and radical action intentions regardless of consensus (the radical action effect was contrary to Mooijman et al., 2018).
Like other research involving antecedents of moral conviction (e.g., d’Amore et al., 2022; Wisneski & Skitka, 2017), our focus was on differences between participants. Another way to approach the gap in the literature is to examine whether framing initial values and (no)-consensus can occur within participants. That is, we do not know whether moral conviction per se (at baseline) is sufficient to elicit collective action intention. As such, we will employ multi-group latent change modeling to see the impact of moral conviction on conventional and radical collective action intentions. We investigated this idea in Study 2 in the context of justice for non-human animals.
Study 2
Study 2 tests whether intra-individual changes in moral conviction, conventional and radical action tendencies occur over time in the context of intrinsic values about the factory farming of animals for human consumption. In Study 2, we did not manipulate value frame as in Study 1 and the Preliminary Study (Supplemental Materials) because these studies suggested that intrinsic valuing (not extrinsic) was the key element in attitude moralization. Study 2 therefore focuses on experimentally isolating the effects of intrinsic valuing and consensus on moral conviction and conventional/radical action. The research context involves support for the welfare of animals in factory farms. We chose a different scenario from Study 1 to test whether findings of Study 1 (i.e., increase in moral conviction as a function of consensus) would apply in a different research context and whether increased moral conviction strengthened commitment to conventional and radical collective action.
There have been many times where people have engaged in collective actions on behalf of animal welfare, such as signing petitions and attending protests against the live export of animals (i.e., conventional actions, e.g., Becker, 2018), or even trespassing into factory farms and abattoirs to film the inhumane conditions, sometimes even “rescuing” (stealing) some of the animals (i.e., radical actions, e.g., Bolotnikova, 2023). The notion that animals have moral worth due to their ability to suffer is the basis of the animal welfare movement (Singer, 1995). Literature suggests that animals should have similar or equal rights to a decent life, free from exploitation just like humans because they also suffer pain and emotions like fear (Anomaly, 2015; Bastian, Costello et al., 2012; Bastian, Loughnan et al., 2012; Hodson & Costello, 2012). Hence, animals are perceived to possess intrinsic values, thus harming animals is perceived to be morally wrong (Bastian et al., 2023). In addition to care and concern for the animals, factory farming causes serious environmental problems such as air and water pollution caused by the nitrates from the manure surplus, global warming, and diminished biodiversity (Berndsen & van der Pligt, 2005; van der Zee, 2017).
Participants completed measures of moral conviction about animal welfare, commitment to conventional and radical action (at baseline) and were contacted 1 week later. They were then given a fabricated article to read about factory farming which was framed in terms of intrinsic values. Participants were randomly assigned to a condition where they witnessed consensus on the detrimental effects of factory farming because of the harm to animals, or a condition without consensus. They then completed measures of moral conviction and commitment to conventional and radical action again.
For the measures of moral conviction and commitment to conventional and radical action at baseline and post-test, we computed latent change scores (Reuter et al., 2010) which were used to test the hypotheses below. Recently, Rehren and Sinnott-Armstrong (2023) investigated temporal stability of moral values across two timepoints (6–8 days apart), and found that 30%–56% of participants changed their values. This change suggests that moral issues may be more flexible compared to non-moral issues. Hence, instead of using differences between participants, we employed multi-group latent change modeling (Reuter et al., 2010) to investigate how moral convictions affect conventional or radical actions to support animal welfare overtime.
Based on our reasoning that moral conviction is stronger when values are intrinsically framed and socially shared, we expected a change in moral conviction from baseline to post-test when participants had been exposed to intrinsic values and consensus. Hence, relative to the absence of consensus, when consensus was present, we expected an increase in moral conviction from baseline to post-test which would predict an increase in radical action intention over time (Hypothesis 1). We also expected that an increase in moral conviction from baseline to post-test would predict an increase in conventional action intention irrespective of the presence or absence of consensus (Hypothesis 2).
Method
Participants and Design
Participants (N = 202) were recruited through a professional participant recruitment company, Survey Sampling International (SSI). Participants received monetary reimbursement for their participation (AUD$11; $3 for baseline-test and $8 for post-test). Informed consent was obtained. A total 36 participants were excluded prior to analysis because of not completing the questionnaire (n = 2), failure on attention checks (n = 10), completion took more than 60 min or less than 9 min (n = 24). The remaining 166 participants (84 female and 82 male) were aged 18 to 78 (M = 46.52, SD = 15.96). With this sample size, a regression analysis with 5 predictors (consensus, moral conviction at baseline and post-test, conventional and radical action at baseline), alpha = 0.05, and power = 0.80, would have a sensitivity of detecting a minimal explained variance effect size of f2 = .08, a small to medium effect size (Faul et al., 2007). Most participants identified as a meat-eater or reduced meat intake eaters (91.5%), whereas only small portions of the sample identified as pescatarian (2.4%), vegetarian (4.2%) and vegan (1.8%). The study employed a mixed methods design with consensus as a between-groups factor (present vs. control) and moral conviction as well as commitment to conventional or radical action as within-subjects factors (measured at baseline and post-test). Participants accessed the questionnaire online by clicking a link on the SSI website.
Procedure
To ensure a consistent baseline understanding of factory farming, participants first read a short paragraph explaining what factory farming was. They then completed the key measures. A week later, participants were presented with a fabricated article to read about factory farming which articulated intrinsic-value justifications for supporting the welfare of animals in factory farming (i.e., because of the harm to animals). After reading the article, participants completed comprehension checks to ensure the content was understood. They were then randomly assigned to either the consensus present condition or the control condition. To ensure that a similar length of time was spent considering the issue, participants in the control condition were asked to write down their thoughts about the article. Participants were required to spend 3 min (which was the approximate length of the video) on this task. Thereafter, participants completed the questionnaire and were debriefed.
Measures
All items were measured on a seven-point Likert scale (1 = Strongly Disagree; 7 = Strongly Agree), unless indicated otherwise. Alongside measures from Study 1, we included an exploratory measure of intrinsic value adapted from Hanselmann and Tanner (2008). However, because value framing was not manipulated in Study 2, we did not expect differences between conditions and therefore do not consider value framing in the focal test.
Article Comprehension Check
Two items were used to assess if participants comprehended the information in the value framing article. For example, “What was the name of the spokesperson in the article?” Both questions had three answer choices.
Perceived Consensus Comprehension Check
Two items measured the degree to which participants perceived that the people interacting in the video came to a consensus, r = .87, p < .001. For example, “The people in the recording reached a consensus on the issues discussed”.
Moral Conviction
The same four items as in Study 1 were adapted to factory farming, at baseline α = .94 and at post-test α = .90. As per Study 1, a PCA again confirmed that the intrinsic value endorsement and moral conviction were empirically distinct (see Supplemental Materials).
Conventional and Radical Action Intentions
Seventeen items were adapted from Thomas et al. (2019) to measure intentions to engage in collective conventional or radical action intentions to support animals. At baseline, conventional action intention α = .92, and at post-test α = .91, for example, “I intend to sign petitions relating to phasing out of factory farms”. At baseline and post-test radical action intention, α = .94, for example: “I would participate in a protest which may involve confrontation with the police”.
Results and Discussion
Comprehension and Manipulation Checks
Comprehension checks showed that 97.8% of the participants identified the correct spokesperson and 89.2% comprehended the correct message. In the absence of a baseline interaction, we assessed the efficacy of the consensus manipulation by examining perceived agreement, which was significantly higher than the scale midpoint (4) (M = 6.00, SD = 0.82), t(87) = 22.78, p < .001, 95% CI [1.83, 2.17], d = 2.38. Sensitivity analyses further indicated that identification with people who oppose factory farming was significantly above the scale midpoint, establishing social influence, but did not moderate the main pathways. Full details are provided in the Supplemental Materials.
Correlations and Descriptive Statistics
All inter-correlations are displayed in Table 4 and were significant. Table 5 displays the descriptive statistics for the dependent variables for both the consensus condition and the control condition. For all other variables, there were no significant overall differences between baseline and post-test values or between the consensus and control condition.
Correlations Between Dependent Variables (Study 2).
Note. N = 166. Convent. = conventional.
p < .001.
Means (M) and Standard Deviations (SD) (Study 2).
Note. N = 166.
The interactions between the difference score from baseline to post-test and consensus condition were not significant.
Latent Change Analyses
To test the hypotheses about an increase in moral conviction, conventional or radical action from baseline to post-measure as a function of consensus (present/control), we employed multi-group latent change modeling. Whilst the correlations and condition means test the rank-order stability of constructs (between persons) and/or the overall means, latent change score models reflect changes within person over time. Results of the measurement invariance analyses for moral conviction, conventional and radical action are presented in the Supplemental Materials. Full metric (loadings) invariance and full scalar (intercepts) invariance were achieved for moral conviction, conventional and radical action.
Latent true change modeling builds on confirmatory factor analysis (CFA) in which a latent factor is represented by indicators at different occasions (here baseline and post-test). In latent change modeling, the latent variable at the post-test is a function of the latent variable at baseline and the latent difference (increase or decrease) from baseline to post-test (see Figure 2 for an example). In keeping with the approach adopted in Study 1, we conducted a multi-group analysis (AMOS 27, 300 bootstraps) with consensus (present/control) as the grouping variable to test a model in which consensus would moderate the effects of increased moral conviction on increased commitment to conventional and/or radical collective action.
Measurement model for moral conviction.
As in the previous studies, we first tested a model in which all paths were free to vary. The unconstrained model was fully saturated, AIC = 56.00. The fit indices for the constrained model in which the paths were constrained to equality was not acceptable, χ2(4) = 17.44, p = .002, CFI = 0.865, RMSEA = 0.143, AIC = 65.44. The difference between the models was significant. We tested whether fit improved compared to the constrained model by setting each pathway separately free as a test of moderation of each path. Only the path from change in moral conviction to change in conventional action showed significant change when the path was released, Δχ2(1) = 8.51, p < .001, which improved the model fit significantly, χ2(3) = 8.93, p = .030, CFI = 0.940, RMSEA = 0.110, AIC = 58.93. Figure 3 shows the standardized regression weights for the final model. Although the formal tests of moderation suggested that it was primarily Δmoral conviction → Δconventional action that differed, there were nevertheless notable differences in the regression weights also in the Δmoral conviction → Δradical action path (Figure 3).
Structural model of consensus moderating the effects of change in moral conviction from baseline to post-test on predicting change in collective conventional and radical action intention (Study 2).
Consistent with predictions, Figure 3 shows that the increase in moral conviction from baseline to post-test predicted an increase in radical action intention but this path was only significant when consensus was available, providing partial support for Hypothesis 1 – “partial” because although the path is significant when consensus is present and non-significant in the control condition (Figure 3), the difference between the two was not reliable when the paths were released. Moreover, unexpectedly and contrary to Hypothesis 2, the same pattern occurred for conventional action suggesting that believing that others hold one’s moralized stance is important for both conventional and radical action intention – indeed, the tests of model constraints supported that this difference was reliable.
General Discussion
People show their support for animal and environmental causes through a variety of actions, from sharing social media posts and signing petitions to engaging in civil disobedience and direct action. In the current research we sought to understand the role that different value frames (intrinsic, extrinsic) may combine with consensus about those values to promote moral conviction and, in turn, commitment to conventional or radical forms of action to protect the environment and the animals within it. We proposed that when people oppose violations because they ascribe intrinsic value to the environment and non-human animals, relative to opposition due to economic consequences (extrinsic value), this would lead to enhanced moral conviction – but that this would especially be the case where those worldviews had been validated by others (i.e., via consensus). We also hypothesized that the links between moral conviction and conventional action would be reliable irrespective of the presence/absence of consensus about values but that the perceived agreement of others about the intrinsic, sacred value, would be necessary for moral conviction to shape radicalism.
The results provided partial support for hypotheses, with some intriguing twists. We found evidence that intrinsic values, but not extrinsic values, increased moral conviction to safeguard the environment in Study 1 supporting our hypothesis and consistent also with the preliminary study (see Supplemental Materials). Enhanced moral conviction, in turn, predicted both radical and conventional action to protect the environment from mining. Although the overall tests of the model fit did not support moderation by consensus (present/absent), the simple slopes differed markedly (Figure 1) and the indirect effect of intrinsic values framing on action via moral conviction was only significant when consensus was present (Table 3). Thus, in Study 1, it appeared that consensus helped to strengthen links between intrinsic valuing, moral conviction and – unexpectedly, cautiously– both action outcomes. Study 2 adopted a longitudinal design to model within-person change in moralization about battery farming of chickens as an outcome of intrinsic valuing that was shared by others (consensus present) or not (control). Here, we also showed that links between moralization and conventional action to promote the animal welfare was stronger when a social consensus supported those values – the overall moderation was not significant for radical action, but the pattern of effects again differed markedly between when consensus was present or absent, providing partial support. Thus, results for both studies provided partial initial support for the hypothesis that intrinsic value consensus matters for mobilization (Mooijman et al., 2018) but little support for the notion that it matters more for radical action than conventional action.
Moralization Is Driven by Intrinsic Values and Consensus
This research holds several key implications for our understanding of the nature and consequences of moral conviction in the context of action to protect the natural environment and non-human animals. First, relatively few studies have identified the drivers of changes in moral conviction. Whilst some analyses have focused on the moralizing role of emotions (e.g., Mullen & Skitka, 2006; Wisneski & Skitka, 2017), the results of our experimental between-person (Study 1) and within-person analyses (Study 2) suggest that one root of changes in moral convictions stems from the values that are ascribed. That is, consistent with Skitka et al.’s (2005) analysis of moral conviction as distinct from attitude strength (or attitudinal opposition per se), here we show that the roots of increasing moral conviction (moralization) lie not in the belief that the consequences of an action will be a loss associated with other undesired outcomes (extrinsic value). Rather, moralization occurs when there is a fundamental and permanent loss of an object with intrinsic value, a loss which is perceived as morally wrong (Bastian et al., 2023). A related implication is that attempts to moralize public attitudes and promote support for a specific social or political agenda would do better to draw attention to the importance of protecting entities because of their inherent “sacred” value, than the potential negative or undesired outcomes (i.e., loss of economic opportunity) that come from failure to protect it.
Moreover, our research is novel in addressing the social bases of how people arrive at moralized worldviews (moral convictions). With some caveats given the results of the multi-group tests of moderation, Figures 1 and 3 show that the relationship between intrinsic value framing and consensus is sharpened when participants believed that others share their intrinsic-value position. That is, consistent with the idea that morality plays an important role in regulating communication because it enables people to “reality test” their arguments about right and wrong (Carnes et al., 2015), the presentation of a consensus, in combination with intrinsic-value arguments, also acted to shape changes in moral conviction. Indeed, Study 2 suggested that moral conviction at baseline was not sufficient to predict change in conventional and radical action intentions. Rather, intra-individual changes in moral conviction from baseline to post-test predicted change in both collective action intentions when intrinsic-value consensus was socially shared.
Moralization Is for Action
A related implication is that where intrinsic values are presented, along with consensus, such a combination also appears to create the preconditions for conventional and/or radical action to oppose harm to the environment and the animals in it. These effects may arise because intrinsic value frames evoke relational values tied to connection, care, and responsibility toward nature and animals (Deplazes-Zemp & Chapman, 2021) and activate eudaimonic values, defined as pursuing purpose and moral fulfilment (Winkler-Schor et al., 2020). This links concern for the environment to identity and deeper ideals about a meaningful life, which may increase receptivity to consensus cues and willingness to act when others share those commitments (e.g., Díaz et al., 2015; Mohideen & Heintzelman, 2025; Winkler-Schor et al., 2020). Consistent with analyses that highlight that moral forms of communication help people coordinate their behavior in groups (d’Amore et al., 2022; Ellemers & van den Bos, 2012; van Zomeren at al., 2024), it is notable that the indirect effects of intrinsic values on conventional and radical action via moral conviction were significant in Study 1 (Table 3) only when a consensus was presented. It is therefore likely that the effect of consensus also extends to engagement in conventional action.
With the exception of findings in Study 1 (where moral conviction was associated with radical action even in the absence of consensus), consensus seems likely to play an important role in sharpening the links between one’s personal conviction, and radical action to address that state of affairs. Indeed, our approach is consistent with the analysis of Mooijman et al. (2018), but we extended upon their findings to establish that it is not just any consensus that drives enhanced radicalism: rather, it appears that it is consensus specifically about a position that emphasizes the value and intrinsic worth of environment and non-human animals. Of course, it is also possible that the conditional effects of consensus are not linear. It is possible that people who perceive that no one shares their values or commitment (i.e., who perceive no value consensus) may be more likely to take radical action because they have “nothing to lose” (Scheepers et al., 2006). Future research could consider whether consensus has a quadratic effect on radicalism such that it is associated with radical action when it is both low and high but not moderate. Nevertheless, both findings support the crucial role of debate and reflection in mobilizing collective radical action. The findings suggest that the effect of consensus spreads not only to commitment to radical action but also to conventional action (e.g., Thomas et al., 2014). Findings support the important role of knowing what relevant others think and intend to do, as part of the process of mobilization in general (see also van Zomeren at al., 2024) but extend these frameworks to the environment and non-human animal domain.
Having said this, in Study 1, moral conviction predicted radical action intention irrespective of consensus. A possible explanation for this finding is that Study 1 was conducted during a period of heightened protest and radical actions which were given extensive media coverage (Gartland, 2017; Robertson & Siganto, 2018; Zając, 2018). Such media coverage about the growing radical anti-Adani actions may have reduced the capacity for our consensus manipulation to have an effect as a moral catalyst for commitment to radical action. When people already know other people’s attitude or opinion (e.g., via media coverage), consensus may be less important for commitment to radical action. Conversely, future research should investigate whether in situations of less knowledge about an issue, people first need to know whether their attitude is shared by others, which then guides their commitment to radical action.
Limitations and Future Directions
In a field dominated by cross-sectional methods, this research is novel in adopting experimental methods to study moral conviction and (conventional and radical) collective action. Our use of more contemporary longitudinal modelling approaches in Study 2 also allows us to study within-person changes in moral conviction (in keeping with theorizing; see Livingstone, 2014). One limitation is that our theoretical rationale for consensus was informed by arguments about the interactive, dynamic and communicative aspects of morality (Bloom, 2010, above). Yet, our manipulation of these was to present participants with vignettes of other people interacting (following Mackie & Cooper, 1984) which is not the same as allowing people to engage in live, unmoderated interaction. Future research should consider the interactive and negotiated nature of moral positions by examining actual interaction (e.g., Thomas et al., 2022; people may engage in different forms of action such as conventional and radical actions simultaneously). Moreover, another limitation of the consensus manipulation is that consensus regarding the value framing is not the only aspect that differs between the consensus and control conditions. That is, the mere presence of others engaging with the topic, or the articulation of arguments made in line with the article’s framing may be responsible for the observed effects. This raises the possibility that participants are responding not only to perceived agreement but also to social interaction and argument exposure more generally. As such, future studies should include a condition where a consensus is not reached in order to isolate the specific effects of consensus. Introducing a condition with interaction but without consensus would allow researchers to determine whether agreement itself, rather than the presence or content of others’ discussion, is the primary driver of the effects.
In addition to this limitation of consensus, future research could examine when exposure to consensus backfires. In the preliminary study (Supplemental Materials), we observed that moral conviction was a weaker predictor of engagement in conventional action when exposed to consensus about conventional action compared to the absence of consensus. It is possible that the presented consensus elicited reactance against consensus about conventional action. Reactance can occur when persuasive messages are perceived as threats to individuals’ freedom to behave in whatever way they wish which can cause diminished willingness to stick to the message (e.g., Dillard & Shen, 2005), here consensus about conventional action.
Another limitation of our research is that we presented the framing of intrinsic and extrinsic values as mutually exclusive forms; we used either an intrinsic or an extrinsic frame for opposition to harm the environment or non-human animals. However, Bastian et al. (2023) showed that there are situations in which intrinsic values can go together with extrinsic values. For instance, someone studies psychology because of enjoying learning about the topic (intrinsic value) and wanting to secure a good job (extrinsic value). Furthermore, literature on relational values suggests that people may value things like the environment because of their relationship with it. Hence, future research could consider all three (intrinsic, extrinsic, relational) values together to provide a more comprehensive understanding of values-based framing and implications for action to promote environmental justice and justice for non-human animals. Finally, given the known difficulties associated with shifting moral conviction (see Skitka et al., 2021, who emphasize that moral convictions are resistant to social influence and pressure) and that it is also plausible that moralization can change how an issue is valued, making it feel objective, obligatory and non-instrumental in ways that resemble sacred or intrinsic worth (see Skitka et al., 2021), future research could model moral conviction, intrinsic/extrinsic valuing and action outcomes over time so that the potential for mutual reciprocal effects can be assessed.
Concluding Comments
We opened this paper with some recent examples of radical climate activism. Our analysis identifies the role of (intrinsic) value framing and consensus in directly and interactively shaping moral conviction and, therefore, action. Are these the ingredients that recently drove climate activists to throw food at famous paintings? The activists expressed their opposition to climate change by pointing out that millions of people are dying in monsoons, floodings, wildfires and severe drought, reflecting the intrinsic harm caused by the climate catastrophe (i.e., intrinsic value framing). Opposition to climate change has been validated by other activists as evidenced by actions in different European countries and Australia (providing evidence of consensus). It seems likely that such actions will continue or increase in the absence of concerted international efforts to cut emissions and address the harms done to non-human animals and the environment.
Supplemental Material
sj-docx-1-eab-10.1177_00139165261442028 – Supplemental material for Intrinsic Value Framing and Consensus Increase Commitment to Radical Action to Protect the Environment
Supplemental material, sj-docx-1-eab-10.1177_00139165261442028 for Intrinsic Value Framing and Consensus Increase Commitment to Radical Action to Protect the Environment by Lucy H. Bird, Mariette Berndsen, Silas Ellery, Alison J. Clark and Emma F. Thomas in Environment and Behavior
Footnotes
Ethical Considerations
The studies involving human participants were approved by an Australian Social and Behavioural Research Ethics Committee (Study 1 and 2, Project number: 8065) and an Australian Human Research Ethics Committee (Preliminary Study, Approval 2014/124). The participants provided their written informed consent to participate in each study.
Funding
The authors disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: Both studies were funded by the Australian Research Council Early Career Researcher Award (DECRA) DE120101029, awarded to the second author.
Declaration of Conflicting Interests
The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
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