2.1 A Deepened Understanding of Existing Concepts

Following Moody-Adams (Reference Moody-Adams1999, p. 169), we use a deepened understanding of a concept to refer to a fuller appreciation of its internal structure and range of application. Buchanan and Powell (Reference Buchanan and Powell2018) provide several prominent cases where such conceptual improvements constituted moral progress. One example they point out is the deepened conceptual understanding of justice (Buchanan & Powell, Reference Buchanan and Powell2018). Historically, we have broadened the domain of justice, or in other words, the range of beings whom we recognize as deserving of justice and rights. Moreover, we have also extended the scope of justice, namely, the range of behaviors, social practices, and institutions that we understand as being subject to scrutiny in terms of justice. This extension signifies that a greater range of actions and social structures, including societal distribution schemes and epistemic practices (e.g., Rawls Reference Rawls2020; Fricker Reference Fricker2007), can be assessed from the perspective of justice.

An enhanced grasp of non-moral concepts can also constitute moral progress. One instance, as pointed out by Buchanan and Powell (Reference Buchanan and Powell2018), is the evolution of our concept of institutions. For large swaths of history, entities that we now recognize as institutions, such as slavery, were categorized as inherent parts of nature. Such categorization led people to believe that these entities were unalterable and inevitable, resistant to significant modification by human choice. Perceiving significant aspects of the social world as institutions, then, can have, and has had, profound implications. If they are indeed human creations, they can, in principle, be altered or even replaced with new institutions by human action—and it makes sense to ask whether they morally should be. When systems like slavery, serfdom, or absolutist monarchy were not considered institutions but taken to be inherent features of nature, they were largely shielded from moral criticism. This allowed such systems to persist unchallenged, perpetuating injustices that could otherwise be addressed through institutional change. After refining our concept of institutions and redrawing the boundary between human creations and natural phenomena, these formerly unquestioned systems became objects of moral examination and social reform. We began to judge them as unjust, unfair, and inhumane, prompting significant efforts to eradicate them from human society.Footnote ²

Deepening the understanding of a concept, as per our theory-theory framework, involves a process where an already existing mental theory underlying the concept is reshaped and refined. In the case of the concept of justice, there has been a significant shift in beliefs about which beings are subject to considerations of justice, and which aspects of the relations among beings might give rise to issues of justice. Emerging beliefs elucidate the internal structure of the concept of justice and explain why certain properties, such as protecting animal welfare and ensuring due weight is given to one’s testimony, are integral to this concept. As regards the concept of institutions, there has been a shift in the belief about how to delineate between this concept and its contrasting concept, nature. Consequently, we now recognize that several social arrangements, which we had once thought to be inherently natural, are actually institutional constructs.

To sum up, changes in the beliefs underlying the concepts of justice and institutions respectively refined the mental theories underlying these concepts, constituting a deepened understanding of the concepts, and in so doing, constituting moral progress.

2.2 The Creation of New Concepts

We have, of course, generated many novel concepts, including, for instance, the concepts of sexual harassment, epistemic injustice, and disability rights. These new concepts have imbued formerly nebulous experiences or emerging phenomena with significant moral implications, empowering us to properly assess and react to them.Footnote ³ The creation of fresh concepts represents the second form of conceptual improvement that might constitute moral progress.

The development of feminist concepts provides a significant instance of how moral progress though conceptual creation has occurred. Until 1993, marital rape remained legal in parts of the U.S. (Bergen & Barnhill, Reference Bergen and Barnhill2006). In 1975, 12 percent of married or cohabiting women reported partner violence (Straus & Gelles, Reference Straus and Gelles1986). About 40 percent of women in federal workforce surveys between 1980 and 1994 experienced sexual harassment (U.S. Merit Systems Protection Board, 1995). As Gloria Steinem (Reference Steinem1995, p. 161) said, “Now, we have terms like sexual harassment and battered women. A few years ago, they were just called life.” Despite the ongoing prevalence of sexism, sexual harassment, domestic violence, and other injustices perpetrated against women, it is heartening to observe that these actions are no longer unexamined or beyond reproach. They have become objects of scrutiny and criticism, recognized by some as wrongful attitudes and behaviors that warrant rectification.

The rise of feminist concepts can be largely attributed to the introduction of consciousness-raising groups into the U.S. women’s liberation movement in 1969, initiated by a group named Redstockings (Keane, Reference Keane2015, p. 189). The consciousness-raising sessions utilized the strategies and networks previously established by the civil rights movement in the 1960s, inviting young women to share their personal experiences of oppression in group settings. Prior to the creation of the concepts of sexual harassment, marital rape, and sexism, individual women lacked the conceptual resources to describe their experiences in concise and meaningful ways, much less in ways that carried moral significance. Consciousness-raising groups served as a medium of communication, enabling oppressed women to articulate their individual suffering. Such communicative activities allowed them to recognize that their individual experiences had numerous shared properties, thereby fostering a collective understanding of the various distressing aspects of their lives, including the typical characteristics of these wrongs, their causal mechanisms, and their usual perpetrators. Ultimately, the act of naming carved out these aspects into distinct categories, such as sexism, marital rape, and sexual harassment. These names organized and solidified the collective understanding into specific clusters of beliefs about the internal structures of various gendered wrongs, thereby forming the mental theories underpinning the concepts of sexism, marital rape, and sexual harassment.

This process of forming mental theories for, and concepts pertaining to, distressing experiences—once concealed by the taken-for-granted flows of life—effectively objectified these experiences. In other words, once these experiences were encapsulated by concepts, they transitioned into thinkable, cognizable objects. Thinking about these objects enabled these oppressed women to understand the root cause of their painful emotions, such as anger, self-doubt, self-belittlement, among others. This helped them differentiate justified feelings (like anger and resentment) from those that were misplaced (such as self-doubt and self-belittlement). As Webb Keane puts the point,

Moreover, the actions objectified by these newly forged concepts could no longer evade scrutiny. Sexism, for example, forfeited its guise of being a natural occurrence, and instead became an object of stern criticism. Most importantly, the introduction of a new concept into common language focused public attention on previously overlooked but widespread facets of life. It redefined a set of common experiences as something needing examination, and provided the public with succinct linguistic expressions to discuss and examine these experiences. Public discourse and criticism have subsequently exposed the widespread and severe nature of these oppressive practices, compelling society to reflect on the social conditions that foster gendered wrongs.

According to our theory-theory framework, the creation of a new concept involves the emergence of a mental theory for a category that hasn’t previously existed. Unlike the concepts of justice and institutions, there had not previously been a mental theory about the typical characteristics, causal mechanisms, and usual perpetrators of behaviors like sexism, marital rape, and sexual harassment. Instead, a collective understanding of the shared characteristics of these gendered wrongs developed through the communicative activities initiated by consciousness-raising groups. And it was not until various categories of misconduct were distinctly named that the collective understanding of women’s suffering evolved into differentiated and organized mental theories of various gendered wrongs. The creation of the concepts of sexism, marital rape, and sexual harassment constituted moral progress by enabling us to identify many previously elusive gendered wrongs.

One objection is that the creation of new concepts should not be categorized as a distinct type of conceptual improvement, since creating any concept can be seen as deepening the understanding of familiar concepts that can be used to express the new concept (Moody-Adams Reference Moody-Adams1999, footnote 8). On this view, for instance, the concept of patriarchy might be seen not as novel but as a refinement of our concept of unjust domination—a way of better understanding who can be victims of injustice.Footnote ⁴ We concur that creating a new concept can result in a deeper understanding of some of its related or constituent concepts—patriarchy, for example, can deepen our understanding of unjust domination. Nonetheless, there are two interrelated reasons to think that the creation of a subordinate concept is not equivalent to deepening our understanding of its superordinate concept.

First, the mental theory underlying the concept of patriarchy is neither merely a subset of, nor reducible to, a refined version of the mental theory underlying unjust domination—the theory one might hold after deepening one’s understanding of unjust domination along gendered lines. The latter mental theory consists in a cluster of generic beliefs about the essence of unjust domination at large, rather than specific beliefs about the essence of patriarchy. For instance, the theory may include asymmetries of power, lack of legitimacy, absence of recourse or resistance, and violations of moral equality, as the core explanatory principles for why a given relationship counts as unjustly dominating. The theory may further posit that relations across racial, generational, or gendered lines can be instances of unjust domination.

In short, the mental theory of unjust domination does not include beliefs about the typical characteristics and causal mechanisms of patriarchy, or about the usual profiles of its perpetrators and victims. These are the elements that constitute the internal structure of the subordinate concept patriarchy and distinguish it from other forms of domination. For example, a mental theory of patriarchy might include more specific beliefs about gender-based hierarchies, the naturalization of male authority, the gendered division of labor, and the socialization of individuals into culturally prescribed roles of masculinity and femininity. It may also incorporate causal mechanisms such as women’s economic dependence, political marginalization, and exposure to gender-based violence, as well as the role of institutions (e.g., the family, religion, and media) in sustaining these dynamics. These beliefs contain substantial content that cannot be inferred from the generic theory of unjust domination. It is plausible to think that this specific mental theory is what is operative when we identify instances of patriarchy in practice. To be clear, this is not to deny the value of a deepened conceptual understanding of unjust domination: it allows us to situate patriarchy within a broader moral framework, linking it to familiar patterns of moral reactions and established practices of redress associated with unjust domination more generally.

The second, related reason concerns explanatory directionality—both causal and justificatory. Given that a mental theory of a subordinate category cannot be reduced to that of a superordinate one, in many cases it is the formation of the former that enables us to refine our understanding of the latter, not vice versa. In other words, the creation of a subordinate concept can explain how and why we come to a deeper grasp of the superordinate concept. For example, the initial release of iPhones, along with the mental theory associated with them, reshaped our conceptual understanding of the phone. Phones are no longer conceived merely as tools for remote voice communication; instead, they are now understood as multifunctional digital devices integral to everyday life—encompassing social networking, navigation, photography, personal organization, and more. The conceptual innovation introduced by the concept of iPhones thus retroactively transformed the broader concept of phones itself.

A subordinate mental theory can also justify the refinement of its superordinate counterpart. For instance, beliefs about the essential features of patriarchy exhibit significant theoretical overlap with other forms of unjust domination. This overlap provides reasons for expanding our conceptual understanding of unjust domination to include gendered relations. Similarly, the belief that patriarchy can persist without physical violence justifies excluding physical coercion as an essential feature in our mental theory of unjust domination. By contrast, while a refined conceptual understanding of unjust domination may help explain why patriarchy is morally objectionable and how it should be addressed, it does not, by itself, justify beliefs about the specific features that distinguish patriarchy from other forms of unjust domination.

2.3 An Enhanced Ability to Apply Concepts

An enhanced ability to apply concepts refers to a refined capacity to discern and foreground features in the world that, according to one’s existing mental theory underlying a certain concept, warrant its application to specific entities.Footnote ⁵

A clear example demonstrating the link between improved conceptual application and moral progress can be illustrated as follows. Imagine an individual who believes that causing excessive suffering to animals is unjust, yet does not see practices like factory farming and bullfighting as unjust. This may be because, due to social conventions, prejudices, inattention, or other factors, they either fail to notice the suffering imposed by these practices on animals or downplay that suffering. Suppose that motivated by a friend’s advice or a revealing documentary they begin to explore the disturbing realities of these practices. Consequently, they become more aware of and assign greater salience in their consciousness to the suffering animals endure in these practices, leading them to recognize them as unjust. This heightened sensitivity and improved ability to apply the concept of justice represents a significant step in their moral progress.

The distinction between a deepened understanding of a concept and an enhanced ability to apply it lies in whether an individual has undergone changes in the mental theory underlying the concept. For example, the mental theory underlying the concept of justice includes beliefs about which types of beings are subject to considerations of justice. If an individual changes their belief from thinking only human beings qualify as objects of justice to including non-human animals, they modify their underlying theory and thus deepen their conceptual understanding of justice. Conversely, even with this deeper comprehension, they might still fail to notice or downplay the suffering that animals endure in certain established practices. When they become more able to discern and foreground the features of these practices that warrant the application of the concept of justice, their ability to apply it is enhanced even though their concept hasn’t been deepened.

This distinction can be further clarified as a type and token difference. When an individual deepens their understanding of a concept, their conception of a type changes—such as their beliefs about its characteristics, their interrelations, and the type’s relationship to others. By contrast, when someone enhances their ability to apply the concept, they become better at noticing features they were previously ignorant of, or perceive them with greater salience, enabling them to better identify tokens of the type. For example, a botany student might know from textbooks that wild carrots are marked by small white umbel flowers with a single tiny purple flower at the center. However, in the field, they may often fail to observe this feature. As their observation skills improve, even though their knowledge of the type remains the same, they become better at identifying tokens of wild carrots.

The ability to apply concepts can even sometimes be elevated in an instant. Amidst the calamitous events of the Second World War, an incident occurred involving a young Jewish girl, Renée Lindenberg (who was around four or five years old). Some villagers were heartlessly suggesting that she be thrown into a well. Fortunately, they were overheard by a woman who responded, “She’s not a dog after all.” Lindenberg’s life was spared (Gilbert, Reference Gilbert2010, pp. xvi–xvii). Arguably in this case, the woman’s intervention was successful in saving the young girl’s life by transforming the villagers’ categorization of her from something casually disposable to a fellow human being. In all likelihood, the villagers had become desensitized to the girl’s human characteristics, adhering instead to the prejudice that she was a creature distinctly different from themselves. Arguably, the woman’s comment helped the villagers see the girl differently (Murdoch, Reference Murdoch2001).Footnote ⁶ Representing the girl as a fellow human, as a moral being, insofar as that is what they came to do, imposed certain moral constraints on the villagers’ behaviors towards the girl. This was due to their existing mental theories underlying the concept of human beings. Once the applied the concept of human beings to her, other concepts come to bear on the girl, while the application of other concepts became unacceptable. She was not to be purged or cleansed anymore. On the contrary, it was arguably a moral obligation to not only spare but positively save her life. Footnote ⁷

An enhanced ability to apply concepts can also be aided by external societal mechanisms. A notable instance is the widespread use of the #MeToo hashtag on various social media platforms. In the 1970s, U.S. feminist movements were pivotal in creating the concepts of sexual harassment and sexual abuse. But there were downsides of employing these concepts, including not being believed, victim shaming, retaliation, and societal stigma. The #MeToo movement, a pivotal campaign against sexual abuse and harassment that allows individuals to share their experiences, emerged against this backdrop. Initiated by New York women’s advocate Tarana Burke in 2006, the phrase #MeToo was meant to unite and support women who had suffered sexual violence, communicating a message of solidarity. In 2017, a New York Times exposé on Harvey Weinstein’s misconduct, voiced by actors like Ashley Judd and Rose McGowan, galvanized many to disclose their stories (Kantor & Twohey, Reference Kantor and Twohey2017). Actor Alyssa Milano then popularized the #MeToo hashtag on social media, initially perceiving it as a means to raise awareness and foster a community among survivors. Milano’s tweet led to nearly a million mentions of the hashtag on Twitter within 48 hours, and the movement quickly spread to Facebook, with about 4.7 million users engaging in 12 million posts in less than a day (CBS News, 2017). Even years later, the hashtag #MeToo continues to resonate on social media, allowing survivors to share their experiences (Gordon, Reference Gordon2023).

The use of the hashtag significantly aided in publicizing personal stories of sexual harassment and abuse, revealing the widespread nature of sexual misconduct and enhancing the public’s capacity to apply the concepts of sexual harassment and abuse. As a result, empathy for survivors increased, catalyzing a shift in societal attitudes and perspectives. This transformation prompted updates and enactments of pertinent laws and policies, reduced the stigma around discussing these topics, and fostered the development of safer environments for open conversations (Gordon, Reference Gordon2023).

Within our theory-theory framework, an enhanced ability to apply a concept, whether it stems from individual or collective efforts, does not involve alterations in the mental theory underlying the concept. Instead, this improvement stems from a refined capacity to discern and foreground certain information about the world that the theory requires to justify the concept’s application. For example, the villagers mentioned above did not change the underlying principles they held to explain what properties were crucial for being a human being, why these properties mattered and how they interrelated, as well as the relationship between the concept of human beings and other concepts, such as moral concepts. The woman’s words allowed them to foreground the girl’s human traits central to their existing theories of human beings. Similarly, the widespread use of the “#MeToo” hashtag enabled the public to discern and foreground cases of gendered wrongs.

It could be argued that the #MeToo movement has also deepened people’s conceptual understanding of sexual violence. We recognize this: as a widespread movement exposing a vast array of information, the #MeToo movement certainly has altered people’s mental theories of various gendered wrongs. According to our theory-theory framework, the mental theory underlying a concept is open to modification as new information and experiences are absorbed. This suggests that, in practice, two types of conceptual improvements may often occur together within the same historical process. However, we can theoretically distinguish between them based on whether the assimilated information modifies the mental theory. By the time of the #MeToo movement, for instance, many still believed that only women could be victims of sexual violence (Maier, Reference Maier2024; Weiss, Reference Weiss2008). Accounts from male survivors challenged this core belief, prompting the removal of gendered assumptions from the concept of sexual violence. By contrast, other garden-variety reports from victims merely exposed previously invisible information that justified applying the concept to unacknowledged cases.