PHI 420/591 The Common Ground

Spring 23

Marcello Di Bello -

Th 1:30-4:15 PM in Tempe, COOR 3301 3323

Office hours: Thursday after class or by appointment


This seminar examines the idea of the common ground as a condition for meaningful disagreement, valid reasoning, rational inquiry about matters of fact, and political decision-making. The motivation for thinking about the common ground stems from the growing political polarization on issues such as climate change, vaccines, abortion, race, the 1619 project, #MeToo, and more. This polarization in people’s opinions, commitments, and values exists alongside deep divisions in wealth, education, housing, health, lived experiences. Seeking a common ground is sometimes touted as the solution to the problem of polarization, and the lack of a common ground as its cause. On the other hand, attempting to overcome polarization by seeking a common ground is sometimes considered the wrong way of addressing the problem. But what is a common ground, in the first place? If it is the solution to polarization, what kind of common ground should we be seeking? Is a common ground even possible or does it necessarily lead to the exclusion of people’s identities? This seminar examines these questions from a philosophical standpoint. It will not offer answers, but rather, a framework of analysis.


This course is meant for advanced undergraduates and graduate students. You will become familiar with different conceptions of the common ground in various sub-disciplines of philosophy. The goal is to understand these conceptions and utilize them to illuminate trends in society and politics today. You will sharpen your critical thinking skills, in reading and writing, for the analysis of theoretical concepts and their application to current social and political questions. You will read academic papers in different sub-disciplines of philosophy—philosophy of language, logic, epistemology, moral, social and political philosophy, post-colonial theory—and develop an appreciation for their distinctive contribution.

Course Materials

Readings and other course materials are available on this website. For readings covered by copyright, please check the Canvas page for this course.
Course materials are divided into “essential” and “additional”. You are only expected to study the essential ones, but I recommend that you have a look at the additional materials for at least one or two weeks.



Please attend class regularly and participate (10% of our grade). This is a “seminar style” course. You are expected to take an active role in the discussions. Please study the assigned materials before class and be ready to discuss them.


In addition, you should write ten Pass/Fail précis as well as three graded essays or a research paper (90% of your grade).


Every week please write a one-page précis of one of the papers assigned for that week. The précis should describe: (a) topic of the paper; (b) main thesis (or main theses, if there are more than one); (c) supporting arguments; (d) objections to these arguments, complications or difficulties that the author considers (if any). Submit your précis each week through Canvas before the beginning of class. You should receive a PASS in at least ten précis, or else a full letter grade will be subtracted from your final grade: A would become B; B would become C; etc.


There will be three main graded assignments for this course, 5 pages each.

1. Write a critical response to one of the philosophy papers you read. Your response should contain a careful summary of the the specific thesis and argument of the paper you want to criticize (1-2 pages). After that, you should explain, in great detail and with painstaking precision, why you disagree with the paper’s thesis and argument (3-4 pages). Please select a paper you disagree with. If you agree with everything you read, please come talk to me.

2. After doing independent research, collect and summarize a case study that illustrates the idea of the common ground (or lack thereof). The first part of your essay (1-2 pages) should describe your case study. Topics for your case study could include, but are not limited to, debates about abortion, vaccine, race, climate change. The second part (3-4 pages) should use some of the course readings to analyze your case study from the point of view of philosophy of language, logic or epistemology.

3. Write a philosophical argumentative essay that attempts to answer the question “What Is the Common Ground and Why Does it Matter?” In answering the first part of the question, I recommend that you focus on a specific notion of the common ground, as is discussed in philosophy of language, logic, epistemology, social and political philosophy, or post-colonial theory. In answering the second part of the question, I recommend that you draw from current trends in society and politics. You may (but need not to) build on the case study you discussed in your second graded assignment. You are encouraged to think critically about the common ground, highlighting its positive as well as its negative implications.

Research paper

If you are a grad student or advanced undergrad with research experience, you may combine the three 5 page essays into one 15-20 page research paper. The research paper should engage closely with a subset of the course materials including the additional ones. It is neither necessary nor recommended that you use materials outside those already included in the course materials.

Please come talk to me before you start working on the research paper.


Week 1 | Week 2 | Week 3 | Week 4 | Week 5 | Week 6 | Week 7 | Week 8 | Week 9 - Spring Break | Week 10 | Week 11 | Week 12 | Week 13 | Week 14 | Week 15 - Workshop | Week 16 |



Week 1: Introduction

The need for a common ground can manifest itself in different areas of human engagement. We will focus on four in particular: communication, reasoning, rational inquiry about the world, and political deliberation. These four areas fall (roughly) within the purview of four sub-disciplines of philosophy: philosophy of language; logic and argumentation theory; epistemology and philosophy of science; and finally, value theory, including moral, social and political philosophy. To these four, we will add a fifth area of investigation, what we might call the question of inclusion and belonging.

The readings in this course are organized systemically to cover different areas of philosophy. In the first class meeting, however, we will read beyond philosophy. We will consider a family of explanations for why our society is divided and polarized, focusing on the logic of market capitalism, the principles of liberalism, the legacy of racism. They all place blame, to different degrees, on individualism and the loss of a sense of community. These explanations are not meant to be exhaustive or definitive, but simply a starting point for the conversation. We will return back to them throughout the course. The philosophical readings that follow about questions of language, logic and reasoning, rational inquiry and political deliberation can all be situated within these overarching explanations.

Essential readings


Week 2: Communication

The first perspective on the common ground—and perhaps the most basic—is that the common ground is what allows us to communicate meaningfully with one another. In this sense, it comprises rules of communication, the meanings of words, and shared beliefs. But the common ground can also be what makes possible more divisive forms of communication, such as hate speech. In this sense, the common ground is shared by a select group of people, not everybody. This raises the question, whose common ground are we talking about? Does it even make sense to talk about a common ground that is shared by all?

Q&A with Sam Berstler

The first part of the class will consist in a Q&A session with Sam Berstler, a philosopher at the Massachusetts Institute of Technology whose research in philosophy of language examines the question of the common ground. She is the author of one of the readings assigned for today. Please come prepared to ask questions.

Essential readings

Additional readings and materials


Week 3: Radical Interpretation

What if your interlocutor spoke a radically different language so that you could not understand what they say? This is the problem of radical interpretation. To carry out a translation, one needs to figure out what the other person means, and in order to figure out what the other person means, one needs to figure out what they believe. Without a grasp of what they mean or believe, no translation seems possible. To avoid this impasse, the principle of charity might help, that is, to assume that what we believe is what others would believe in similar circumstances. This putative similarity of beliefs can then be used to carry out a translation. If this is right, the challenge of radical interpretation might not be too radical in the end. We share more with others than we might have thought.

Essential readings

Additional readings and materials


Week 4: Incommensurability

In grappling with the problem of radical interpretation, we did not take seriously the possibility that other people could hold radically different conceptions of the world. They could carve out the world, so to speak, in radically different ways from us. If that is so, how could we assume—as the principle of charity does—that we all share the same beliefs? The absence of a common ground, from a linguistic and conceptual perspective, is what is sometimes called incommensurability. There are many forms of incommensurability: linguistic, conceptual, moral, etc. We will focus primarily on linguistic and conceptual incommensurability, but also consider its social implications.

Q&A with Elizabeth Povinelli

The first part of the class will consist in a Q&A session with Elizabeth Povinelli, an anthropologist at Columbia Universality and a filmmaker. Her paper on the anthropology of incommensurability is one of the readings assigned for today. Please come prepared to ask questions.

Essential readings

Additional readings and materials


Week 5: Logic and Argumentation

The second perspective on the common ground we will examine has to do with logic, reasoning and argumentation. It would seem that, in virtue of sharing certain principles of reasoning, we can debate, disagree and resolve our disagreements. And yet, it is surprising hard to justify even the most basic logical principle of all, the principle of non-contradiction—that one should not assert p and its negation at the same time. And, more recently, some logicians have even come to endorse logical pluralism, the view that in fact there can be a multiplicity of logical principles. Perhaps, then, we should not aim to find a common ground by attempting to justify logical principles. Turning from logic to argumentation theory, a more feasible approach might be to settle, in a dialogical setting, on argumentative rules that make rational inquiry possible. But what does that require, exactly?

Q&A with Nathan Ballantyne

The first part of the class will consist in a Q&A session with Nathan Ballantyne, a philosopher at Arizona State University. His paper on the fog of debate is one of the readings assigned for today. Please come prepared to ask questions.

Essential readings

Additional readings and materials


Week 6: Skepticism, Tradition and Common-sense

We now turn from logic and argumentation theory to epistemology. From an epistemological perspective, it is common ground we should be responsive to evidence if we aim to figure out what the world is like. But the skeptic will ask, why should we be responsive to evidence? Scientists themselves have suggested that common rules and practices used to gather, analyze and draw inferences from evidence more often lead to falsehoods rather than truths. These claims might be exaggerated, but even if they are, the skeptical doubt remains. For how can we claim that being evidence-responsive is truth-conducive without, in a circular manner, appeal to evidence?

Instead of attempting to ground our epistemology from first principles, the common ground could include a reference to common-sense and traditions rooted in history. But this would seem a capitulation of reason and would still leave open the question, why should we follow common-sense or tradition in the first place? Why should that be our common ground? The skeptical challenge persists.

Essential readings

Additional readings and materials


Week 7: Rational Polarization

The challenge of skepticism stands unanswered, but its significance should not be exaggerated. Perhaps, those who doubt the effectiveness of vaccines or challenge the evidence about climate change are skeptics who doubt the principles of scientific inquiry. Admittedly, this is a far-fetched explanation for belief polarization. The challenge of skepticism has always been with us. Polarization, instead, is a phenomenon more circumscribed and historically situated.

Let us assume—optimistically—that people are often willing to engage in an empirically-informed rational inquiry in which they share criteria for assessing the strength of their evidence. And yet, even people who share the same evidence and the same standards for assessing it might end up endorsing radically different positions—a phenomenon that has been called “rational polarization”. How widespread or worried we should be about this phenomenon is another matter. Is rational polarization the most plausible explanation for widespread polarization? This is hard to say, but there is empirical evidence that rational polarization plays an important role in explaining actual belief polarization.

Q&A with Kevin Dorst

The first part of the class will consist in a Q&A session with Kevin Dorst, a philosopher at the Massachusetts Institute of Technology whose paper on rational polarization is one of the readings assigned for today. Please come prepared to ask questions.

Essential readings

Additional readings and materials


First essay due

Week 8: Bubbles and Chambers

Another explanation for belief polarization is that—because of the structure of information cascading on social media—people will have selective access to information and inhabit epistemic bubbles and echo chambers (though the two are different). Echo chambers and bubbles are failures of common ground in the sense that people do not share the same evidence. Given these circumstances, then, belief polarization is inevitable, and in many ways, unsurprising. The cure is simple: escape your epistemic bubble and echo chamber; go talk to those with whom you disagree; etc. As we will see, though, it is much harder to escape an echo chamber than an epistemic bubble.

Essential readings

The Epistemology of Disagreement

Additional readings and materials


Week 9: Spring Break, No class


Week 10: Epistemic Injustice

Epistemic bubbles and echo chambers are ecosystems of information, with their own internal rules and regulations. They constitute, in some sense, a common ground, at least for those inside them. A common ground, then, can also exclude, and perhaps it needs to exclude in order to include. So what happens when some people—along with their knowledge, evidence, testimony, experience—are excluded? Recently, a number of philosophers within the analytic tradition have theorized about “epistemic injustice”in various forms: testimonial, hermeneutical, oppressive. Long before these discussions in analytic philosophy, one of the foundational texts of post-colonial theory took up the question whether certain voices are systematically excluded from the conversation—and cannot even articulate their position.

Essential readings

Additional readings and materials


Week 11: Overlapping Consensus

We now turn from the epistemological to the political. Citizens in liberal democracies often hold radically different views about the good life, religion, education, the common good. A question that has shaped political philosophy in the analytic tradition over the last three decades is, how can political deliberations and judicial decisions be carried out—and be legitimate—despite the fact of radical disagreement about matters of values among the citizenry? One answer is that, in the end, reasonable people will share a political common ground, an “overlapping consensus”, which makes possible the exercise of public reason and its legitimacy.

On this view, an important qualification must be made: an overlapping consensus must be sought between reasonable people. Those who are “unreasonable” do not enter the overlapping consensus, and thus are not entitled to pursue objections that may threaten the integrity and legitimacy of public reason.

Q&A with Jonathan Quong

The first part of the class will consist in a Q&A session with Jonathan Quong, a moral and political philosopher at the University of Southern California whose work on unreasonable citizens is one of the readings assigned for today. Please come prepared to ask questions.

Essential readings

Additional readings and materials


Second essay due

Week 12: Self-organization

The idea of an overlapping consensus presupposes that there is a minimal, essential set of values that we share (or procedures that we endorse), despite deep, widespread disagreement on many issues. But one wonders whether this overlapping consensus exists, and even if it does, one wonders whether it can ever be enough to give legitimacy to political deliberations. Another model suggests we need not worry about whether we have an overlapping consensus. A convergence might emerge, not as a matter of theoretical commitments to shared values, but as a self-organizing order of preferences, behaviors and practices.

Essential readings

Additional readings and materials


Week 13: Individualism and conflict

The ideal of an overlapping consensus (as well as the idea of a self-organizing convergence) must confront the reality of increasing conflicts, division, partisanship in our political lives. Perhaps, deep structural reasons are the cause, and these cannot be easily overcome by invoking a common ground. A couple of hypothesis are worth exploring here. First, an individualistic, competition-driven market logic that extends everywhere ends up pitting people against each another. Second, political deliberations are inherently conflictual: friendship can exist only against the background of enmity.

Essential readings

Additional readings and materials


Week 14: Trust and Civility

If we still think that the ideal of an overlapping consensus and public reason are good ones—we might not—the question is how to regain a functioning public reason via targeted interventions. One proposal focuses on reestablishing trust, between people of opposing views and between citizens and public institutions. Another proposal emphasizes the virtue of civility. These proposals are not exclusive, and they both underscore that attitudes toward each other—not only an agreement about content—are essential for a functioning public reason.

Q&A with Cheshire Calhoun

The first part of the class will consist in a Q&A session with Cheshire Calhoun, a moral and political philosopher at Arizona State University whose work on the virtue of civility is one of the readings assigned for today. Please come prepared to ask questions.

Essential readings


Week 15: Workshop

Students will workshop their research papers by giving short presentations accompanied by either a handout or slides and followed by Q&A. Each presenter will have 15 minutes to be split between the presentation itself and Q&A at the discretion of the presenter. The list of presenters is below:

1:30 | Angela | title tba

1:45 | Andrew | Marked By An X: The Influence of Counterculture to A Better Common Ground

2:00 | Cole | Common Agreement and Endoxa

2:15 | Georgia | title tba

2:30 | Kevin | title tba

15 minutes break

3:00 | Nicholas | title tba

3:15 | Paola | Ethics of Common Ground

3:30 | Scout | Contradictory Common Ground

3:45 | Vanessa | title tba

4:00 | Yashin | Against Hermeneutical Justice: The Self-Sufficiency of Being


Third essay or research paper due

Week 16: Conclusion

What have we learned about the common ground? What questions are still left open and what lines of inquiry seemed more promising?

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