ANNOTATED BIBLIOGRAPHY

Polarization and its Causes
Please note: As some literature contains information pertinent to both the causes of
polarization and strategies to help overcome it, entries in this document may be repeated in
the Strategies to Help Overcome Polarization annotated bibliography. These entries are
noted with an asterisk (*). With entries listed in both annotated bibliographies, we have
endeavoured to describe the parts of the source document that pertain to causes of
polarization in the first bibliography and the parts pertaining to strategies for overcoming it in
the second.
Berreby, D. in The Agenda with Steve Paikin. (2018, February 1). The psychology of tribalism
[Video interview]. TVO Today. https://www.tvo.org/video/the-psychology-oftribalism
Canadian scholar David Berreby notes that “it’s not the same issues that make people
crazy” in different parts of the world. In Europe, there is a polarized debate about
GMO’s; in North America, people are not so exercised about that. In the US, it’s gun
control, whereas in most of the world, gun control is a question for rational
deliberation about what we can do to keep people safe – an administrative domain.
Rational conversation still happens around some issues, and these are geographically
specific. Therefore, it’s not the issue per se, or debates over factuality, that drive
polarization. Rather, Berreby explains, it has more to do with identity: “what you’re
signalling to other people about who you are.” It also does not have to do with
educational attainment. For example, Berreby references Dan Kahan at Yale, who has
found that climate denial is more likely in people with higher levels of education. On
the positive side, tribalism can be undone by working on common projects.

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Bird, S., Gattinger, M. & Lachapelle, E. (2020, January 8). On energy and climate, we’re actually not so
polarized. Policy Options. https://policyoptions.irpp.org/magazines/january-2020/on-energyand-climate-were-actually-not-so-polarized/
This article presents broad findings from a survey of Canadians in September 2020. It helpfully
differentiates between fragmentation of opinion and polarization, the former occurring when
there is a range of viewpoints present and the latter being defined by very strong differences
concentrated at both poles on a spectrum. This means that people don’t just disagree; they do
so strongly. On the subject of a national carbon tax, Canadians’ opinions were found to be more
fragmented than polarized, but an analysis of the data along partisan and regional lines revealed
polarization. Conservatives and residents of Alberta, Saskatchewan, and Manitoba held opinions
more strongly opposed than others. The article reports that “opinions on pipelines are clearly
fragmented, but perhaps not as polarized” as we might think. The article concludes with an
interesting observation: that “a minority Parliament risks amplifying regional tensions,
intensifying partisan polarization and furthering perceptions that Canadians are polarized.”
Bromwich, J. (2018, June 28). Everyone is canceled. The New York Times.
https://www.nytimes.com/2018/06/28/style/is-it-canceled.html
This article explores the current cultural phenomenon of “cancelling” celebrities when
audiences (or at least some followers) decide they disapprove of something the celebrity has
said or done. Quoting various academics who define cancelling as “a cultural boycott,” “an
expression of agency,” and “an agreement not to amplify, signal boost, give money to” said
celebrities, the author traces the phenomenon to its early uses by Black Twitter users. Originally
intended to be humorous, it then grew in popularity as a way for people to control content on
social media and demand accountability from people who have said “socially irredeemable
things.” Questions are raised about the performativity of cancelling and the relative importance
of addressing individuals who say offensive things and changing institutions that have “stripped
people of their humanity – the latter being far more destructive.”
* Brubaker, D. R., Brubaker, E. N., Yoder, C. E., & Haase, T. J. (2019). When the center does not hold:
Leading in an age of polarization. Fortress Press.
Chapter 1: Understanding Polarization - David R. Brubaker defines polarization as a longexisting phenomenon of human conflict that has changed over time. It is characterized by
divisive affiliations or forming “camps” with like-minded people and an unwillingness to
consider the views of others (p. 13, p. 16). He believes that the combination of income
inequality, an identity threat, and an articulated grievance is the “formula that consistently
produces a polarized society (or organization)” (p. 24). He presents a list of the ten most likely
causes of polarization: economic inequality, identity threats, racism and racial inequality, sexism
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and gender inequality, differing moral universes, global nationalism, balkanized media, political
structure, social sorting, and leadership-driven polarization (pp. 14-23).
Chapter 2: Leadership and Polarization describes five characteristics that are likely to occur in
polarized environments: (1) personal attacks (from belittling to physical assault); (2) holy war
(describing conflicts in epic terms); (3) distorted information; (4) relentless obsession; and (5)
intractable negotiations, in which compromise becomes unthinkable (p. 33). Brubaker discusses
how different types of leaders experience polarization, including business leaders;
congregational leaders with issues such as women’s rights, LGBTQ+2S, abortion, war, racism,
etc.; leaders of not-for-profit organizations regarding advocacy for immigrants, prisoners, etc.;
and governmental leaders at all levels who make major public-policy decisions (p. 37-38).
Brubaker quotes Eastern Mennonite University President, Loren Swartzendruber, on what
leaders need to do to transcend polarization: “Leading in an age of polarization means that we
need to practice the art of non-anxious presence... In the face of conflict, we have a tendency to
either leave the conflict or take on the anxiety, and neither of those options is good. The most
successful leaders stay in the conflict, they don’t run from it, but they refuse to take on the
anxiety of the system” (p. 32).
Chapter 3: Communicating Across the Divide – by David Brubaker and his son, Everett
Brubaker. This chapter focuses on communication and the polarizing limits of everyday
language, why and how it occurs, and some solutions (e.g., deliberative dialogue). Language is
not a neutral medium, so we need to take a mindful approach to language. For example, by
using language that describes or reflects spectrums rather than sides (and everything inbetween). It is critical to use words that are grounded and unpacked, as a lot of difficult
language is abstract. The more concrete the language is, the more understandable it is.
Conversely, abstract language can lead to misunderstandings. In deliberative dialogue and
mindfulness, we think about what we’re trying to say and the implications of the language. We
can unpack how we go about it – the main elements of communication being the message, the
messenger, and the audience. These questions set the tone: How does the message get framed?
Who is sharing the message? What is their credibility or legitimacy? Who is the audience?
Traditionally, we debate when communicating across the divide. It is extreme and polarizing.
Alternatively, we can deliberatively dialogue.
Chapter 4: Trauma, Polarization, and Connection – by Carolyn Yoder. Yoder defines trauma as
an individual’s or group’s responses—physical, emotional, cognitive, spiritual, and relational—to
“traumagenic” events or unjust systems (p. 68). “Traumagenic” means “likely to cause trauma to
the people who are targeted, the perpetrators, and the witnesses” (p. 68). She urges people to
look at trauma, encouraging the examination of polarization through a trauma-informed lens, as
unaddressed trauma may lie at the root of many of our polarized social systems. Trauma

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responses manifest as: social engagement (a physiological response that signals a bid for
connection); mobilization (fight/ flight response), and immobilization (freeze/collapse response).
Chapter 5: Weathering Polarization with Resilience – by Teresa J. Haase. This chapter examines
the tools needed to combat polarization. Haase notes that increases in polarization have in turn
caused higher levels of social and political stress. To combat political, economic, and societal
polarization in the most extreme times, people do better when they employ resilience.
Chapter 6: Transforming Polarization - This chapter discusses how polarization operates at
multiple levels: the intrapersonal (inside of us), the interpersonal (between us as individuals),
and the organizational or congregational level. If we are to significantly reduce polarization, the
author claims we will need to rebuild spaces of community (social and religious), citing
alienation and the decline of religion as major factors that have contributed to our current
climate.
Carothers, T., & O’Donohue, A. (2019, October 1). How to understand the global spread of political
polarization. Carnegie Endowment for International Peace.
https://carnegieendowment.org/2019/10/01/how-to-understand-global-spread-of-politicalpolarization-pub-79893
This article details the global spread of political polarization. The authors acknowledge how
polarization has become a problem that negatively impacts democracies around the world, from
India to Poland, Brazil to Turkey, and in the United States. According to this article, in recent
years, research shows that populist and illiberal leaders are putting democracy in danger. As we
live in the age of social media, opposition leaders make flames, as well as responding with
antidemocratic and confrontational tactics of their own. Sometimes growing the economy
would ease polarization, but it is not suitable for all countries. The presidential system leads to
abuse of executive powers and promotes a toxic view of the president, rather than the country
as a whole. In the cycle of rising polarization, there have been attacks on the judiciary which
creates divides in society and as a result, leads to the demonization of activists and human rights
defenders. In countries like the United States, we see that intense partisanship has become an
inherent part of both social and political life.
Crosby, A. (2021). Policing right-wing extremism in Canada: threat frames, ideological motivation, and
societal implications. Surveillance & Society, 19(3), 359-363.
https://doi.org/10.24908/ss.v19i3.15007
This article is about extremism in Canada, and details the increase in prejudice and extremism
towards minority groups in Canada in recent years. Examples include anti-immigrant rhetoric,
hate crimes, and racist activity experienced by Muslim, Asian, and Indigenous peoples in
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Canada. Such anti-immigration sentiment and hate towards minority groups highlights two
types of polarization: affective (e.g., increased hatred towards those perceived as the “other”)
and ideological (e.g., between religious groups, and globalism versus nationalism).
* Dutton, W. (2017, May 5). Fake news, echo chambers and filter bubbles: Under-researched and
overhyped. The Conversation (Canadian edition). https://theconversation.com/fake-news-echochambers-and-filter-bubbles-underresearched-and-overhyped-76688
Reports on a study carried out in seven nations (United States, Britain, France, Germany, Italy,
Poland, and Spain) in January 2017. It found that, contrary to widespread concerns about the
internet only reinforcing existing beliefs, internet users are using online search engines to “burst
filter bubbles and open echo chambers.” Surveying 14,000 internet users, the researchers found
that fears around search algorithms are exaggerated, and that the most motivated users are in
fact exposing themselves to diverse viewpoints and using search engines to fact-check
information.
* French D. (2020). Divided we fall: America's secession threat and how to restore our nation. Macmillan.
This book is a dire warning of what may happen if we can’t find the courage to reconcile across
difference. French discusses aspects of social discourse and the cultural changes that are feeding
polarization. The author introduces the idea of the “Overton window” - a “concept that refers to
the range of acceptable political discourse on any given topic” (p.86). The key to shifting policy
lies not so much in changing politicians, but in changing the terms of the debate. In other words,
“the window shifts to include different policy options not when ideas change among politicians,
but when ideas change in the society that elects them.” (p. 86). French argues that “the forces
pushing the right edge of the Overton window have grown so strong that on many issues
they’ve pulled the window apart. There is no longer a single window; there are two. Negative
polarization means that the two windows are moving away from each other so fast that it’s now
difficult to engage in even the most basic of good-faith conversations on some of the most
critical issues that define American politics” (p. 89). Moreover, “if you believe your opponent’s
views are outside the realm of acceptable discourse, it’s a very short trip to conclude that they
shouldn’t enjoy the right to speak at all” (p. 92).
French also talks about “rising cultural hostility” toward free speech, particularly among youth
(p. 93). He says that anger at tragic and criminal events – e.g., the Parkland shooting – can lead
to intense opinions, and to a sense that “conversation is useless. Only power matters now” (p.
90). Unfortunately, says French, the people who care the most about politics, who drive the dayto-day national conversation, give no quarter to opponents. They condemn any effort at
moderation and believe that the very effort to see whether there is merit in an opposing view
necessitates dangerous compromise and accommodation.

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* Harwood, R. C. (2022). Civic virus: why polarization is a misdiagnosis. The Harwood Institute for Public
Innovation. https://theharwoodinstitute.org/civic-virus-report
The Harwood Institute is a research organization in the United States that “equips people,
organizations, communities, and networks with the tools to bridge divides, build capacity, and
tackle shared challenges.” They have been analyzing American perceptions on “the state of the
nation, their lives, and hopes and concerns” since 1990 (p. 7). This report summarizes the
findings of their case-study research undertaken in 2021 with “16 in-depth focus groups that
make use of a typology of different US communities.” (p. 2). Their key findings are that social
and psychological conditions (e.g., fear, anxiety, and a lack of belonging) are contributing to
societal divides more than ideological polarization (p. 2). However, it is agreed that polarization
is intentionally being fueled by leaders and media (news and social) (p. 2). This situation is
confusing, disorienting, and destabilizing for people, and so they respond with their fight-orflight instinct, by engaging in tribalism, or by not engaging at all (p. 2). People are afflicted with
feelings of anxiety, anger, fear, confusion, isolation, loss of control, helplessness, and
hopelessness (p. 2). The COVID-19 pandemic is understood to have exacerbated these
conditions (p. 2), yet again, “the partisan divides we see today seem more about people wanting
to ‘belong to a team’ than about adhering to any political party ideology” (p. 3). This societal
impasse lessens our ability to dialogue and problem-solve, and we frequently debate “race and
systemic racism, growing disparities in society, climate change, police brutality and safety, and
entitlement” without solution (p. 3). We don’t feel safe to approach or engage those with
differing views for fear of arguing, harm to personal safety, or “being invalidated, shut down, or
ostracized” (p. 3).
* Hoggan, J. (2019.) I’m right and you’re an idiot: the toxic state of public discourse and how to clean it
up. New Society Publishers.
This book by James Hoggan, Canadian public relations specialist, summarizes interviews with
public figures to examine what causes the degradation of public discourse and present
solutions. Some of the interviewees are psychologists, philosophers, feminists, researchers, and
more. Polarization in the public square is defined by how we blind ourselves to the perspectives
of others through the stances we take against them, and how these biases and judgements
interrupt lines of communication and lead to gridlock. Polarization prevents us from collectively
problem-solving through various psychological “inaction and denial cycles” (p. 26). Such
concepts include the advocacy trap (progressively seeing others as our enemies), cognitive
dissonance (holding onto old beliefs because letting go hurts our ego), tribalism (teaming up
with some and pulling away from others), confirmation bias (finding information to affirm our
beliefs), and motivated reasoning (ignoring information contradictory to our beliefs).
* Itten, A.V. (2018). Overcoming social division: Conflict resolution in times of polarisation and
democratic disconnection. Routledge.

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According to Anatol Valerian Itten, it is not only the case that society has become more
fragmented and politics more polarized over the past decade or so; we are also losing the ability
to bridge our divides. Disrupted and increasingly dysfunctional societies suffer from frustration,
disconnection, fragmentation, polarization and escalation. Itten writes, “Agreed-upon social
rules and norms become suspended, misinterpretation and unpredictability govern, and the
malfunctioning of democratic processes coopts other parts of society” (p.2). We come to
believe our fellow citizens believe more extreme things than they really do. But with public
conflict resolution and mediative decision-making, we can learn to find common ground, even
on controversial issues. The book contains strategies and conditions that are important for
mediative interventions to be successful in overcoming social divisions.
Iyengar, S., Sood, G., & Lelkes, Y. (2012). Affect, not ideology: A social identity perspective on
polarization. Public Opinion Quarterly, 76, 405-431. https://doi.org/10.1093/poq/nfs038
This article (note date: 2012) addresses the debate between “maximalists” who argue that the
policy preferences of United States citizens identifying as Democrats and Republicans have
become more extreme, and “minimalists” who argue that most Americans remain centrists but
partisanship and ideology are becoming more tightly associated where partisanship refers to
party preferences in voting and ideological differences refer more to positions that people hold
in relation to policy, which often are not that far apart between the two main parties. The
authors argue that policy attitudes have less explanatory value than the nature of political
campaigns. Consequently, the apparent increasing polarization is of more of an affective nature
(partisans dislike each other more) than it is one of differences related to policy. They trace this,
in turn, to political campaigns that attack opponents and reinforce biases held by partisans on
both sides.
* Kenyon, T. (2014). False polarization: Debiasing as applied social epistemology. Synthese, 191, 2529–
2547. https://doi.org/10.1007/s11229-014-0438-x
The author defines “false polarization (FP)” as an “interpersonal bias on judgement, the effect of
which is to lead people in contexts of disagreement to overestimate the differences between
their respective views.” (p. 2529). The author argues that both polarized beliefs and a false
perception of polarization can reduce the chance of finding common ground and engaging in
productive discussion (p. 2530). The causes of FP are “overestimat[ing] the extent to which...
actual views differ,” or seeing others as biased, dishonest, or coy (not coming out and
articulating extreme views) (p. 2531). Prior studies, such as that of Robinson et al. (1995),
suggest that “mutually perceived opponents” do not believe they can find common ground as a
starting point for resolving differences and are therefore reluctant to dialogue (p. 2532). This is

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echoed by Pronin et al. (2002a), who suggest that differing viewpoints can be amplified by FP
and result in each side seeing the other as “extreme, unreasonable, and unreachable” (p. 2532).
LaHurd, C. S. (2018). Fifty years of American polarization and the changing roles of faith communities.
Dialog, 57(1), 23-30. https://doi.org/10.1111/dial.12373
Carol Schersten LaHurd points out the correlations between political polarities and geography,
race, gender, ethnic origin, sexual orientation and social class. That these correlations exist
supports that idea that our ideological differences originate in very different life experiences
and worldviews (p. 24). LaHurd quotes political commentator Fareed Zakaria who asserts that
increasingly partisan differences are often seen in moral terms: “People on the other side of the
divide are not just wrong and to be argued with. They are immoral and must be muzzled or
punished.” To counter stuck polarities, LaHurd suggests a generative polarity, which involves
“helping partisans on both sides come to better appreciate how each side needs the other's
challenge and support” (p. 27).
Lees, J., & Cikara, M. (2021). Understanding and combating misperceived polarization. Philosophical
Transactions of the Royal Society B. https://doi.org/10.1098/rstb.2020.0143
At the outset, the authors remind us that “there is a temptation when we think about
polarization and its negative consequences to champion inter-partisan harmony, but a wellfunctioning democracy requires disagreement and debate” (p. 1). The authors have
"construct[ed] a typology of psychological and intergroup phenomena that, while distinct, have
all been labelled ‘polarization’.” However, the term ‘false polarization’ is misleading: polarization
is a real, measurable phenomenon in the world... what is false is people’s beliefs about the
extent of that polarization” (p. 1). For this reason, the authors "argue that the term ‘false
polarization’ should be replaced with ‘misperceived polarization’” (p. 2.) “The term ‘false
polarization’ seems to have arisen from research on ‘naive realism’ showing that partisans
overestimate disagreement with outgroups” (p. 2).
The authors characterize actual polarization as objective attributes of people and intergroup
relations in two categories: individual positions and intergroup gaps (p. 2). Individual positions
include affective polarization (e.g., extreme prejudice towards or the dehumanization of an
outgroup), ideological polarization (e.g., an individual’s extreme position about an issue), or
identifying as a part of a like-minded group (e.g., tribalism) (p. 2). Other times polarization
occurs at the intergroup level – where a “gap in ideology, outgroup attitudes, or ingroup
identification between parties” occurs (p. 2). Conversely, ‘false polarization’ or ‘misperceived
polarization’ is characterized as the subjective perceptions of people and intergroup relations in
two categories: “inaccurate first-order beliefs about how others identify or how far apart two
groups are on an issue (e.g., a perceived partisan gap), and inaccurate second-order beliefs

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about what others think about oneself and one’s group (meta-perceptions)” (p. 3). The authors
caution that these meta-perceptions (inaccurate intergroup beliefs) reinforce a cycle of
misperceived polarization and lead to actual polarization (p. 7).
Mason, L. (2018). Ideologues without issues: The polarizing consequences of ideological identities. Public
Opinion Quarterly, 82, p. 866–887. https://doi.org/10.1093/poq/nfy005
Liliana Mason discusses the distinction between ideology and identity based on political party
identification in the United States. Curiously, she observes that affective polarization (e.g.,
dislike and loathing) seems to be driven by identity elements more than by divergent attitudes
to policy. That is, affective polarization is occurring in spite of relatively low levels of
disagreement on social and political issues that have remained more or less unchanged for
decades. This was apparent in Donald Trump’s “post-ideological” campaign, which was
“relatively devoid of coherent policy prescriptions” (p. 867). Mason attributes “value-free” social
distance more to a sense of inclusion/exclusion and finds that it is “the ‘otherness’ of ideological
opponents, more than issue-based disagreement, that drives liberal-versus-conservative rancor”
(p. 867). In other words, the reasons liberals and conservatives dislike each other may be
unconnected to their opinions. Mason cites Achen and Bartels (2016, p. 228) who argue that
“identities are not primarily about adherence to a group ideology or creed. They are emotional
attachments that transcend thinking” (p. 869).
A major contribution of this article is the distinction between ideological polarization (issuebased) and affective polarization (socially and emotionally based). Affective polarization is
driven by “social identities that generate ingroup privilege and outgroup derogation” (p. 870).
Mason asserts that “partisan-ideological sorting and media consolidation…has allowed even
uninformed Americans to know the name of their ideological team. But team names without
issue knowledge can generate political conflict that is unmoored from distinct policy goals” (p.
884). In other words, “the ideological roots of…polarization are largely based in our social
attachments to ideological labels, not…to thoughtful collections of opinions…The passion and
prejudice with which we approach politics is driven not only by what we think, but also
powerfully by who we think we are” (p. 885).
Merkley, E. (2020). Polarization, eh? Ideological divergence and partisan sorting in the Canadian mass
public. [Unpublished working paper].
In this paper, Merkley reports on data from the Canadian Election Study (CES) to measure trends in
ideological divergence, ideological consistency, and partisan sorting amongst Canadians from 19932019. Ideological divergence occurs when we are moving toward ideological poles – i.e., holding
increasingly extreme ideological positions. Ideological consistency means that our issue positions are
consistent with one another (as in, following a similar logic or value set). Partisan sorting means that

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partisans are becoming more ideologically distinct from each other, and that our partisan preferences
correlate logically with our policy beliefs or ideology.
The author concludes that Canadians are not becoming more ideologically polarized but are becoming
modestly more consistent in our ideological beliefs, and much more sorted accordingly: “Left-right
ideology is intertwined with partisanship to a degree that is unprecedented in Canadian history” (p.2).
The paper includes an interesting discussion about which is primary: ideology or partisanship. The
author cites research in the United States indicating that partisanship comes first, and that people will
change their beliefs or positions on policy issues to bring them in line with their partisan preferences
more often than the other way around: identity as a Republican or Democrat comes first. There is less
research on whether partisanship is equally powerful in Canada. However, Merkley finds in his
research that opinion change is more common than partisan change, though this difference is smaller
when it comes to immigration, same-sex marriage and income inequality.
While the paper doesn't explore affective polarization, the author notes both that affective
polarization can be driven by partisan sorting, and that other researchers have found it to be
increasing in Canada. This raises concerns about “biased information processing, heightened demand
for partisan news, more social distance or alienation between partisan groups, and perhaps more
contentious political discourse” (p.15). The author concludes by saying that the scale and scope of
polarization as a phenomenon in Canada has yet to be determined.
Moore-Berg, S., Hameiri, B. & Bruneau, E. (2020). The prime psychological suspects of toxic polarization.
Current Opinion in Behavioral Sciences, 34, 199-204.
https://doi.org/10.1016/j.cobeha.2020.05.001
Samantha Moore-Berg and co-authors cite research in four Western countries finding that “as
differences of opinions on social issues become more pronounced, distrust of political
opponents increases” (p. 2). They extend the list of drivers of polarization to include
dehumanization and negative ‘meta-perceptions’–inferences about what other groups think—in
particular, what they think about the ingroup. Dehumanization dynamics are very concerning:
“…on both sides of the ideological spectrum [political partisans] attribute more animalistic traits
to political outgroup members and explicitly view political outgroups as less than fully human.
Dehumanization is also particularly strongly correlated, among both Republicans and
Democrats, with support for spiteful activities associated with toxic polarization” (p. 3).
Moreover, “how much each group thinks they are dehumanized by the other informs how they
evaluate that group, in turn” (p. 3). These meta-perceptions are subject to a pessimism bias:
“We think that outgroup perceptions about the ingroup are more negative than they are in
reality” (p. 4). This has the unfortunate effect of increasing hostility between groups. The fact
that the phenomenon is symmetrical for Democrats and Republicans suggests that shared
psychology may be more to blame than “divergent ideological convictions” (p. 1). More
hopefully, the authors also note the existence of a false polarization bias - the finding that the
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ideological divide on a range of issues is perceived by both sides to be greater than it is in reality.
Reducing negative meta-perceptions requires a different approach than does reducing negative
perceptions and suggests that a rapprochement is more possible than we might believe.
Paas-Lang, C. (2019, Sept 12). Canadians are polarized, and intense party loyalty could be to blame:
Study. Global News. https://globalnews.ca/news/5892865/canada-polarization-study/
This brief news item covers the release of a report by the Digital Democracy Project (see DDP’s
Research Memo #3). While the report found little evidence of polarization being caused by
social media, it did document increasing affective polarization among Canadians, as determined
by measures of the warmth gap (comparing levels of like/dislike toward ideological allies as
compared to opponents); the affect gap (which indicates strength of association of positive or
negative words with a respondents’ own party and other parties); and social distance (e.g., how
comfortable respondents would be having someone from a different social group as a friend,
neighbour or in-law).
Pinker, S., & Wood, J. Jr. (Host). (2021, June 2). Cancel culture, communication, & the quest for
humanism. [Podcast episode]. Braver Angels. https://youtu.be/QxkU_Rsgn8c
John Wood Jr. (Braver Angels) interviews Steven Pinker, who claims that the nature of the news
causes us to feel our institutions are failing and that everything is getting worse, even when
there is data showing progress. Pinker suggests that a sense of unjust inequity - unfairness leads to discontent. Although he cites Thomas Sowell’s explanation of left and right positions on
human nature (are we ‘infinitely malleable’ or ‘fatally flawed’?, respectively) - Pinker believes
both and points to the facts - progress is evident – so what is it about our human nature that has
allowed us to progress?
Polletta, F., & Callahan, J. (2017). Deep stories, nostalgia narratives, and fake news. American Journal of
Cultural Sociology, 5, 392-408. https://10.1057/s41290-017-0037-7
Francesca Polleta and Jessica Callahan discuss claims that the phenomenon of “Trumpism” can
be pinned on right-wing opinion media. They point out the pedagogical role political
commentators across the political spectrum have taken in instructing viewers how to interpret
the news, thus replacing conversation among real people, which has become more and more
fraught for those on right and left alike. The authors cite research showing the power of the
stories we tell each other which “serve to reinforce collective identities and ‘us vs them’ binary
thinking”: “The use value of the story in reinforcing a partisan political identity was more
important than its truth value” (p. 11). They also cite literature on rumours and how they
produce solidarity and group identity, while encouraging people to engage in “blunt expressions
of anger” (p. 404). They write, “When we see the options only as people being duped by Fox
News or speaking from their lived experience…[w]e miss the fact that people often interpret
outrageous stories as evidence of a broader phenomenon; stories about the way the world used
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to be often conflate history and nostalgia; that people’s relationship to media commentators
affects what they take from the stories they hear; and that stories may have political impact less
by persuading than by reminding people which side they are on” (p. 14). Fortunately, the
converse is also true: storytelling may also hold promise as a route out of polarization.
Public Policy Forum. (2019a). DDP Research Memo #3: Polarization and its discontents. Digital
Democracy Project. https://ppforum.ca/articles/ddp-research-memo-3/
The Digital Democracy Project (DDP) is a project of the Public Policy Forum, an organization
bringing together leaders from Canadian businesses, federal, provincial and territorial
governments, academic institutions, unions, and non-profit organizations to discuss governance
and contribute to public policy. Using a definition of polarization as “the segmenting of society
into increasingly isolated and mutually incomprehensible political tribes”, the DDF conducted a
survey and an analysis of online data to try to determine whether social media and its echo
chambers were drivers of polarization. They found – rather surprisingly – that the data did not
support that conclusion. Instead, they found ideology and partisanship to be the biggest drivers.
Data from Twitter showed that partisans are most likely to follow only candidates from their
own parties and that very few Canadians favour highly partisan media outlets. The project did,
however, find evidence of affective polarization – “dislike of parties or their supporters on the
other end of the political spectrum simply because they belong to an opposing group—among
the Canadian public.” This can be contrasted to ideological polarization, in which “people hold
divergent views on political issues that don’t bleed into their feelings about the people or
parties that support them.”
Public Policy Forum. (2019b). DDP Research Memo #4: Talking past each other on immigration. Digital
Democracy Project. https://ppforum.ca/articles/ddp-research-memo-4/
The Digital Democracy Project surveyed Canadians for their opinions on immigration and their
populist and nativist (anti-immigrant) tendencies. They found that across the political spectrum,
Canadians hold views on immigration that are still somewhat complex, nuanced, and amenable
to influence, when given the facts. Nativist sentiments were highest among those identifying as
conservatives and those who feel the economy or their personal finances are getting worse.
Partisans did differ in the issues of concern they most associated with immigration. While both
Conservatives and Liberals ranked jobs and the economy as their first concern, Conservatives
were more likely to identify national security, illegal immigration and cultural values as
immigration-related concerns, while Liberals and NDP supporters were more likely to express
concerns about integration and diversity.
Saxe, R. in The Agenda with Steve Paikin. (2018, February 1). The psychology of tribalism [Video
interview]. TVO Today. https://www.tvo.org/video/the-psychology-of-tribalism
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Scholar Rebecca Saxe of the Massachusetts Institute of Technology argues that while our
proclivity to innately care for those close to us is laudable, it can also lead to parochialism (i.e., a
narrowing of our circle of care and concern to those closest to us). Identities are “an act of
imagination” and at any point, any single dimension of identity can be the basis for connecting
with others, or not.
We might think that a simple fix is an exchange of facts, that we just need to share what we
know and/or negotiate: “It’s much harder for people to take seriously the possibility that we
can, in really good faith, have different perspectives on the same situation. So, we revert to an
alternative simple strategy, which is [to write them off as crazy and] suppress [them]… rather
than looking for common ground”.
Sexwélecken. (1900). Re Skú7pecen re Stseptékwlls (The Story of Porcupine). Qwelmínte Secwépemc.
https://www.qwelminte.ca/stseptkwlls
This stseptékwll (oral telling) comes from the Secwépemc (Shuswap) First Nation. According to
Qwelmínte Secwépemc, the story of porcupine “serves as the foundation of reconciliation,
informing how to Walk on Two Legs and come together as two people, to learn from each other
and live as equals in peace and prosperity. Just as Sku7pecen [porcupine] does in his story, we
must walk through the deep snows to bring together two groups of people and ways of
knowing.”
* Silan, M.A.A. (2017, December). Debiasing in the political context or proceeding with political
polarization or surviving and creating change in this political climate. [Unpublished paper].
University of the Philippines Diliman.
Polarization is exacerbated by both confirmation bias, in which we tend to find or notice
information that confirms what they already believe, and disconfirmation bias (aka ‘motivated
skepticism’) in which we spend more time attending to discrepant information, scrutinizing it
and generating arguments to refute it, and becoming more critical of information we dislike
than of information that confirms our beliefs. Consequently, Miguel Alejandro Silan argues
(following Taber & Lodge, 2006) that individuals who are more politically sophisticated are more
prone to attitudinal polarization because they have the cognitive capacity and knowledge
resources to defend their existing beliefs. He also asserts that both liberals and conservatives
are vulnerable to politically motivated reasoning (Ditto et al. 2017).
Silan also points out that not all examples of polarization have been toxic. While polarization
characterized the Third Reich and Rwandan inter-ethnic violence, it has also led to momentous
social shake-ups and/or ‘transformations’ such as the Arab Spring, national liberation
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movements in colonized countries, and contemporary movements against India’s caste system.
Moreover, Silan claims, even the most intense and politically polarizing issues do resolve:
examples include overt and oppressive racism in early 20th century America, the suffrage
movement in the early 20th century and LGBTQ acceptance almost globally during recent years.
Speer, S., & Loewen, P. (2021, February 2). Perceptions and polarization: measuring the perception gap
between urban and rural Canadians. Public Policy Forum. https://ppforum.ca/wpcontent/uploads/2021/02/PPF-Perceptions-and-Polarization-Measuring-the-Perception-Gap2021-EN.pdf
Author Sean Speer, Prime Minister of Canada Fellow, and his co-author Peter Loewen, research
the urban-rural divide in Canada and how we can cultivate greater understanding and respect
among urban and rural Canadians (e.g., through public policy analysis, community engagement,
knowledge translation). Their research centres around the question: How do urban, suburban
and rural Canadians think about one another's circumstances and perspectives? The goal is to
determine if there are differing perspectives on how citizens think, live, and vote, according to
where they live. "There are two key takeaways from this analysis: Canadians perceive
considerable variation between urban, suburban and rural places on issues ranging from ethnic
diversity and economic dynamism to political preferences and social values. Perceptions of
these place-based variations, however, do not differ much among urban, suburban and rural
Canadians." (p. 7).
The authors note how technology (i.e., the internet), political partisanship, and geography can
play a role in causing polarization. They emphasize that another important factor at play is
"people's perceptions about how others live, think, and vote." (p. 8). They found evidence to
suggest that "distorted perceptions not only fuel polarization, but that polarization can in turn
lead to even more distorted perceptions." (p. 10). This cycle, they claim, grows political
polarization and leads to "social attenuation" (reduced or diminished perceptions of risk to
society) (p. 10).
The authors acknowledge a "spike in regional alienation", political extremism and other signs of
[emergent] polarization" being experienced in Canada (p. 6). Through their research, they have
noted "a growing sense that different groups and places have distorted perceptions of one
another's circumstances and perspectives. This "perception gap" can make it challenging to have
cross-cultural dialogue, reach political compromises, and ultimately sustain social cohesion." (p.
6). Their results, however, show that while Canadians from different geographical regions
believe there are significant differences, the magnitude of these perceived differences doesn't
change based on where they reside. This is important because we will feel more divided from
our fellow Canadians if "place-based poles that lack a sense of common experiences and
perspectives" grow (p. 24). The authors consider how public policy can be used to combat this
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phenomenon, such as through the reduction of inequalities (e.g., investment and opportunity in
rural and low-income communities). Thankfully, the authors' research suggests that Canadians
have a small "perception gap": that we share common understandings of how we all think, live,
and vote.
* Stanley, M. L., Sinclair, A. H., & Seli, P. (2020). Intellectual humility and perceptions of political
opponents. Journal of personality, 88(6), 1196–1216. https://doi.org/10.1111/jopy.12566
Matthew Stanley, Alyssa Sinclair and Paul Seli make the argument that in today’s world, there
are many opportunities for people to isolate themselves in cliques of like-minded desired
communities. Unfortunately, this has the effect of shielding us from conflicting views, along with
the reasons, arguments, and evidence supporting those conflicting views. This can “stymie
intellectual development [and] create an environment in which social extremism and political
polarization flourish (Barbera, et al., 2015; Iyengar & Hahn, 2009)” (p. 5). We need to recognize
that social and political disagreement can be useful and fruitful in “generating creative solutions
to significant problems and growing intellectually” (p. 34).
Taibbi, M. (2019). Hate Inc.: Why today’s media makes us despise one another. OR Books.
Author and veteran journalist Matt Taibbi describes how American news journalism has moved
from ostensible objectivity – an illusory objectivity, given the ubiquitous biases and subjectivity
inherent in curating, reporting, editing and presenting the news – toward explicitly partisan
reporting that follows a business model based on addiction, profit-seeking and consumer
ratings. This is summed up in the title of a December 2019 book review by Joseph Hogan,
‘Making Money from Division’ (LA Review of Books). The media, says Taibbi, cultivate audiences
that see the current role of the media as openly cheering for one political side or the other,
something that would have been seen as anathema to journalism even two decades ago. This is
how the news media act as a driver of polarization.
* Sunstein, C.R. (1999). The law of group polarization. University of Chicago Law School, John M. Olin
Law & Economics Working Paper No. 91. https://dx.doi.org/10.2139/ssrn.199668
The focus of this article is on group polarization as it relates to the activity of deliberation as
found in juries, legislative bodies, political organizations, regulatory commissions, multimember
courts, faculties, student organizations, religious sects, and Internet discussion groups.
It provides a good working definition of group polarization, illustrates it in action, and pulls it
apart. Two principal mechanisms underlie group polarization: (1) social influences on behavior;
(2) limited “argument pools,” and the directions in which those limited pools lead group
members. The author further examines social influences as informational and reputational, and
elaborates by a discussion in the literature on cascades. A key difference is that cascade effects
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lead people to fall in line with an existing tendency, whereas polarization leads them to a more
extreme point in the same direction.
* Ury, W., in Davidson, S. (2021). How to talk to an anti-vaxer.
https://www.saradavidson.com/blog/2021/11/how-to-talk-to-an-anti-vaxer
Author Sara Davidson interviewed conflict-resolution expert William Ury. According to Ury,
society is experiencing intractable conflicts, those that are hard to control/deal with because
they are not amenable to compromise. When these conflicts are experienced, we frequently
dehumanize and demonize the others involved. This occurs, in part, because we respond to
emotion more so than reason. When Davidson brings up how this is reflected in politics, Ury
describes the situation as a "... huge problem with toxic emotions, rigid positions, and fierce
fighting."
Wilson, A. in The Agenda with Steve Paikin. (2018, February 1). The psychology of tribalism [Video
interview]. TVO Today. https://www.tvo.org/video/the-psychology-of-tribalism
Anne Wilson, a scholar at Wilfrid Laurier University in Waterloo, Ontario, doesn't think tribalism
per se is on the rise, but the kind of tribalism that exists in political polarization is definitely
rising. Some of this is driven by political actors, but, it started before Trump, making him both
symptom and cause. Wilson asserts that we are actually getting less tribal in some ways (e.g.,
around racial integration, religious pluralism). Some of our sense that polarization is increasing is
imagined; people overestimate how different they are from people on the “other” side. On the
issues that are most important to us (e.g., racism, free speech) we often end up assuming that
everyone on the other side believes the most extreme version of the belief we feel runs counter
to our own, when in fact, it’s really a small percentage of people on both sides that agree with
those types of statements. “We often end up disliking people not because of what they actually
believe, but because of what we think they believe.” Moreover, she says, “our tendency to
hunker down increases under situations of threat…It’s when we are under threat that we go to
the tribe.”
Wilson advocates the Three C’s: We need to curate our social networks (make them wider, let
more people in), communicate better and listen to people outside of ideological divides, and
challenge. The way political actors are behaving is often more polarized than how regular
people are, and if we hear that kind of rhetoric, we should say no to it.
Wilson, A., Parker, V., & Feinberg, M. (2020). Polarization in the contemporary political and media
landscape. Current Opinion in Behavioral Sciences, 34, 223-228.
https://doi.org/10.1016/j.cobeha.2020.07.005

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This article by Wilfrid Laurier University scholars Anne Wilson and Victoria Parker, along with
Matthew Feinberg from the University of Toronto, describes the rise of polarization in the
United States and what they believe to be fueling it. They distinguish several types of
polarization: affective polarization (political animosity), ideological polarization (policy
preferences), and perceived or false polarization (overestimation of ideological divide) (pp. 4-5).
False polarization describes how perceptions are driven more by what people think others
believe, and that such misconceptions often misrepresent the positions of others (p. 5). The
authors suggest that this may be “particularly evident for vivid, extreme, and egregious
opponent positions that characterize the worst of the other side, and less pronounced for more
mundane policy views.” (p. 6). The authors caution that such “mis-calibrated animosity based
largely on illusory rifts might affect a functioning democracy” (p. 6). They argue that
polarization, and the incentive to amplify polarization, is increasing “among political elites,
partisan media, and social media” (p. 7). The authors suggest that affective polarization
contributes to ideological polarization in a “feedback loop starting with institutions stoking
polarization and eventually leading to actual increases in party division over time (which could in
turn further encourage continued polarization among elites and media).” (p. 12). Three
consequences of polarization are identified as reinforcing the feedback loop: cognitive
dissonance, distrust and avoidance of those with opposing views, and the selection of and
reward for those who “express extreme and outrageous views.” (p. 13).
Zakaria, F. (2017, June 15). The country is frighteningly polarized. This is why. The Washington Post.
https://www.washingtonpost.com/opinions/we-dont-just-think-the-other-side-is-wronganymore--we-think-theyre-immoral/2017/06/15/f218c3e4-5207-11e7-be253a519335381c_story.html
Political commentator, Fareed Zakaria, describes the current state of polarization in the United
States and claims it is far more about identity than policy. In the past, American voters tended to
locate their ideological homes by where they stood on economic issues (e.g., taxes, spending,
welfare policy). Today, they define themselves more in terms of identity – gender, race,
ethnicity, sexual orientation and social class, though the latter is rarely named explicitly. This
makes conflicts more intractable, less amenable to compromise, since the middle ground on
moral issues is harder to find. Zakaria argues for pluralism of ideas and opinions, and warns
against the dangers of an increasingly censorial approach to that which either the left or the
right finds offensive, whether that be comments, speakers, theatre or art.

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