It is rare when a book itself marks a liminal moment in human history. Such a claim seems like blatant hyperbole. But The Price of Freedom Denied: Religious Persecution and Conflict in the Twenty-First Century, plus the wider scholarly enterprise underlying it, represents a unique culmination of centuries of thought and struggle against religious persecution and for protection of the rights of conscience, belief, and exercise enshrined in international law but massively violated in the world today.

What makes this book historic is this: for centuries, even millennia, great thinkers have made assertions about the dangers of state favoritism and coercion in matters of religion, along with claims about why people should have the right to peacefully exercise transcendent duties unmolested by political authorities. We now have the means to rigorously test such conjectures. This is what Brian Grim and Roger Finke do. By marshaling unprecedented global data and applying new empirical methods, they not only corroborate hypotheses about the price of freedom denied. They also provide a compelling theory that explains why society works the way it does.

In brief, Grim and Finke probe the question of why religious liberty matters. Their answer is theoretically elegant and empirically powerful: when religious freedoms increase, inter-religious conflict declines, grievances lessen, and persecution wanes. On the other hand, as government restrictions increase—often at the behest of dominant religious groups—so do violent persecution, inter-religious hostilities, and regional strife. Grim and Finke's theory, which explains the interaction between societal pressures and government practices, provides real guidance to policy makers struggling with renascent religious tides.

To understand how this enterprise came about, a bit of scholarly history is helpful. Roger Finke is one of the pioneers of the "supply side" theory of religion, which contends that restrictions that exact costs or barriers to religious suppliers undermine religious vitality. An underlying premise of this paradigm is that the default condition of religion is diversity, which Peter Berger argues is especially true in a globalized era "where everyone is everywhere." A free marketplace of religion, on the other hand, allows the natural plurality of faith expressions to blossom, providing more vibrant religious life and, by implication, more tolerant relations among the faithful.

Grim and Finke explicitly draw out the implications of this framework for understanding religious persecution and relations among religious groups. And here they link their theory to a larger intellectual tradition. While they acknowledge that the foundation for their reasoning is centuries old, they focus on Enlightenment thinkers of the 18th century who explicitly made the case against religious monopolies or cartels and for the peaceful consequences of allowing natural religious diversity to blossom. Voltaire, for example, contrasted the despotism of state-enforced monopoly he saw in France with the peace of plurality he noticed at the Royal Exchange in London. Adam Smith, similarly, contended that if the government allowed religions to operate freely their natural tendency to subdivide would prevent any one or two from dominating society and enlisting the sword of the state to repress competitors. David Hume expanded on this insight by noting that to ensure public liberty, tranquility, and thriving industry, a wise magistrate must avoid extending favoritism to dominant sects and require that they leave each other alone. These sentiments were echoed in America by James Madison and Thomas Jefferson, who argued that state enforced religion not only violated individual liberties but threatened the security of the state. In other words, they saw religious freedom as the anodyne of religious conflict.

Grim and Finke are able to test such propositions—and advance a global theory that explains them—because of a remarkable confluence of their lives as scholars and contemporary developments. As to their lives as scholars, Roger Finke and Brian Grim illustrate the creative burst that comes from an exceptional academic partnership. As a sociologist of religion, Finke not only pioneered the analysis of quantitative data to test theories of religion and the state; he also developed the Association of Religion Data Archives (ARDA) at Penn State. That vast project, funded by the John Templeton Foundation, provided the prodigious data base for his collaboration with Brian Grim.

Brian Grim nurtured his "science" (as he says on his webpage) as a doctoral student of Finke's at Penn State. But he brought to that graduate work two decades of experience abroad as a researcher, educator, and curriculum developer. From 1982 to 2002 he worked and lived in Hong Kong, the Xinjiang province of China, Kazakhstan, Saudi Arabia, the United Arab Emirates (UAE), Germany, and Malta. These experiences gave him an intuitive feel for the impact of state regulation of religion, persecution, and inter-religious conflict. As he has remarked in presentations, when he lived in the UAE, where his Catholic faith was legal, he had many opportunities and high motivation to contribute to that society, both in his work and outside of it. In Saudi Arabia, on the other hand, where his faith was illegal, he had few opportunities to contribute outside work and less enthusiasm for work itself, a pattern that he thinks helps explain the very different trajectories of these neighboring nations.

Working with Finke at Penn State, Grim developed a sophisticated method to code, measure, and develop overall indexes of government and social restrictions on religion in virtually every country on earth, an unprecedented development. He first employed this method in his dissertation, then perfected it as senior researcher for the Pew Forum on Religion and Public Life.

Here is where we see the synergy of political developments, scholarship, and advocacy. What made this scholarly enterprise possible was the massive lobby campaign in the 1990s that produced the 1998 International Religious Freedom Act. A key provision of that act required the U.S. State Department to report annually on the status of religious freedom in every nation. Those reports, which required that our diplomatic personnel investigate on-the-ground conditions of diverse religious communities, improved over time with the critiques of advocacy organizations and the helpful input of country specialists. While other organizations document religious conditions around the world, the State Department report represents the most thorough and systematic effort to date.

Grim seized on these State Department annual reports as a vast data base that could be combed for objective, verifiable evidence of restrictions. Employing a rigorous protocol that codes discriminatory laws and documented incidents of harassment, arrest, property destruction, and violence, he is able to develop credible country measures that can be compared cross-nationally and over time. The genius of this enterprise is that Grim does not attempt to measure some indefinable quality of religious freedom; rather he codes observable and non-trivial restrictions to develop a broader measure, or index, of how religious practice is constrained.

After publishing initial results of this research, Grim was hired as senior research fellow by the Pew Forum on Religion and Public Life, whose director, Luis Lugo, immediately grasped the significance of the coding methodology. Under Grim's direction, the Pew Forum supplemented State Department documents with 15 other reports by the UN, the European Union, other regional bodies, and NGOs, and they expanded the number of coding questions and tested them repeatedly for reliability

The fruit of that operation is illustrated by two reports of the Pew Forum, which provide index scores on government restrictions and social hostilities by country, region, and religion. The 2009 report garnered international attention for its finding that 70 percent of the globe's population lives in nations with high restrictions on religion, while the 2011 report found those restrictions increasing.

As a "Fact Tank" the Pew Forum does not draw causal inferences or normative conclusions from its reports. So while Grim was directing the broader Pew Forum effort, he and Finke were writing The Price of Freedom Denied to test their broader theoretical and normative theory. To do so, they relied on prior coding of 143 countries with a population of two million or more, using State Department reports and a smaller number of coding questions than the subsequent Pew research, which used more reports, a larger number of coding questions, and incorporated smaller countries in subsequent years. While results of their coding for this book are nearly identical with those of the Pew Forum, the public availability of the larger Pew data base provides an extraordinary opportunity for scholars to conduct replication studies—one of the hallmarks of good science—to test the theory presented here.

This brings me to the perennial debate about whether the social sciences can ever be really scientific. While I have fallen on the skeptical side of that debate, The Price of Freedom Denied represents some of the best social science I have ever seen. The project addresses a vital concern, develops a universal theory to explain it, and draws upon global data to test the theory with sophisticated statistical methods and case studies. In other words, it is theory-driven, data-rich, timeless, and real-world in its applications.

But more than this, The Price of Freedom Denied achieves something truly rare in the social world: nomological insight and elegance. Great scientific theories, we learn from the history of science, achieve leverage by explaining more with less, often in counterintuitive fashion. Grim and Finke attain this grail by anchoring their work in several propositions that they rigorously test:

• "to the extent that a religious group achieves a monopoly and holds access to the temporal power and privileges of the state, the ever-present temptation is to persecute religious competitors openly"
• "to the extent that governments deny religious freedoms, physical religious persecution and conflict will increase"
• "to the extent that social forces deny religious freedoms, physical persecution will increase"
• "to the extent that religious freedoms are granted to all religions, the state will have less authority and incentive to persecute religion"

The first three propositions combine to explain a religious violence cycle: Government restrictions on religion trigger strife and hostility among religious groups, which invites more government restrictions, which produces more violent religious persecution. But as the fourth thesis suggests, the vicious religious violence cycle can be broken. When governments relax restrictions on religion and treat all groups equally, grievances lessen and greater societal tolerance and civility ensue, leading to positive cycles where groups channel energies and competition into civil society pursuits. Such a culture, in turn, buoys democratic governance and unleashes economic enterprise.

A theory of such obvious real-world significance deserves the widest exposure and rigorous test and application. Unfortunately, some of the book's methodological underpinnings are contained elsewhere. Likely acceding to the publisher's desire to limit length and cost, Grim and Finke do not provide a full explanation of the coding protocol. Instead, we are referred to the ARDA website. Moreover, while their appendix shows how their structural equation modeling tests the religious persecution model, we are directed to their published articles for further details. Thus it takes a bit of a scavenger hunt to understand fully their procedures.

While this is a shortcoming of the book, in another sense it underscores the opportunity for other scholars to use the broader Pew Forum data base to corroborate or refine their theory. In other words, this book should launch fresh scholarly enterprise. Nothing less will be required to overcome the mental barriers among élite policy makers, opinion leaders, and legal cognoscenti who cannot imagine why one would want to protect or advance something as benighted or divisive as religion.

Nowhere is this task more pressing than in the debate over global Islam, which Grim and Finke tackle in their most bold and controversial foray. They begin by pointing out that violent religious persecution is far more common in Muslim-majority countries than elsewhere and occurs with greater severity. As the 2011 report by the Pew Forum shows, nations that saw increases in religious restrictions from 2006 to 2009 came predominately from the Muslim arc.

The authors examine the common explanations for this pattern—the colonial legacy, despotic regimes, lagging economic development, ethnic conflict—and find them inadequate. Instead they argue that dynamics within the Islamic religion itself help explain this disparity. In particular, they point to Sharia law as inherently conducive to discrimination, religious strife, and persecution. Because religion and law are not separated under Sharia, they argue, and because blasphemy and apostasy are treated as serious offenses in all schools of Islamic jurisprudence, Sharia-based societies represent unique challenges to religious liberty.

Grim and Finke would rest on solid empirical ground if their assertions focused on implementation of strict versions of Sharia, often pressed by militant Islamist movements, which invite harassment by authorities or vigilante repression of religious minorities and dissenters.

But because Grim and Finke implicate broader tendencies within Islam, we see a tension between their data and their argument about Sharia. On the one hand, they strive to avoid being either overly critical or timidly uncritical of Islam by hewing close to their data, and they take pains to demonstrate the diversity of practice in Muslim-majority societies. For example, in sub-Saharan Africa they find low levels of persecution in seven of eight Muslim-majority countries and lower levels of persecution even compared to others in the region. This finding prompts the question of why such societies have not adopted the strict versions of Sharia we find elsewhere in the Islamic arc. Is it because of the influence of Sufi evangelization on the continent? African cultural influences? Some other combination of factors? We also see contrary patterns in Central Asia, where persecution seems to arise from policies of authoritarian regimes fearful of independent Islamic civil society, not Sharia.

Rather than apply their theoretical propositions to explore such variation, Grim and Finke slide into what some might see as an "essentialist" reading of Islamic history and culture. They discuss Mohammad as a law-giver and military leader, probe the emergence of Sharia as a way to govern the expanding lands of Dar-al-Islam, and cite Quranic passages that suggest the merger of law and religion in the faith. Because neither author would claim the credentials of a classically trained Islamic scholar, this historical excursus seems a bridge too far. But this criticism does not undermine their universal theory or the propositions underlying it; on the contrary, it calls for further research guided by their model into the dynamics of Islamic societies, their variation and potential for evolution.

Why, then, is this a liminal book? Because it provides a modern theory and voluminous quantitative evidence for a timeless truth: humans are spiritual creatures who thrive best and most harmoniously when they enjoy the freedom to express their fundamental dignity. This insight suggests a strategic opportunity for policy makers, religious authorities, and civil society leaders groping for remedies to the destabilizing religious strife afflicting the globe. In the place of counterproductive measures of repression (all too often the default impulse), strategies that protect the freedom of conscience and religious practice offer the best means of navigating the crucible of the 21st century: living with our differences in a shrinking world.

Allen D. Hertzke is Presidential Professor of Political Science at the University of Oklahoma. The Future of Religious Freedom: Global Challenges, a collection of essays he edited, is forthcoming this fall from Oxford University Press.

Copyright © 2012 by the author or Christianity Today/Books & Culture magazine.
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