An environmentalist who pursued the ecological impulse of Paganism, from its ancient roots to its modern revival in Europe and North America, discusses his observations about the spirit of Paganism and its influence on everyday Western culture — and even on old-time religion.

Alcoholics Anonymous co-founder Bill Wilson once said that the program he helped create is, “utter simplicity which encases a complete mystery.” Our guests reflect on the Twelve Steps and how they resonate in their personal stories and in Buddhist and Christian teachings.

We received hundreds of essays in response to our query about what anchors and unsettles our Catholic audience. So we asked some of you to speak about your tradition. The moving reflections we heard prompted us to depart from our usual format and bring you a fabric of voices from the Church itself.

In a recent Pew poll, 16 percent of Americans identified themselves as “unaffiliated” — atheist, agnostic, or most prominently “nothing in particular.” Greg Epstein, a Humanist chaplain at Harvard, described himself that way until he discovered the tradition of humanism. He is passionate about articulating an atheist identity that is not driven by a stance against religion but by positive ethical beliefs and actions.

Ingrid Mattson, the first woman and first convert to lead the Islamic Society of North America, describes her experience of Islamic spirituality, which she discovered in her twenties after a Catholic upbringing. We probe her unusual perspective on a tumultuous age for Islam in the West and around the world.

Americans have been hearing a lot about Mormonism in the context of Mitt Romney’s presidential campaign. But much of the public discussion of this faith of 13 million people has focused on controversies in the church’s history. We’ll avoid well-trodden ground to seek an understanding of the lived beliefs and spirituality of Latter Day Saints, with a leading scholar of the church and a lifelong practitioner. Robert Millet describes a developing young religion with distinct mystical and practical interpretations of the nature of God, family, and eternity.

Environmentalism and climate change are hot topics; yet they’re still often imagined as the territory of scientists, expert activists, and those who can afford to be environmentally conscious. We discover two people who are transforming the ecology of their immediate worlds in Dunn, Wisconsin and New York’s South Bronx.

The greatest threat in the post-Cold War world, says Douglas Johnston, is the prospective marriage of religious extremism with weapons of mass destruction. Yet the U.S. spends most of its time, resources, and weapons fighting the symptoms of this threat, not the cause. The diplomacy of the future, he is showing, must engage religion as part of the strategic solution to global conflicts.

The second program in our series on guiding figures in what some are calling the “post Religious Right era.” This program’s guests are conservative Evangelicals who are increasingly being watched by a new generation of Christian and secular leaders. They want to move beyond the partisan and cultural divides of recent years to fight poverty, AIDS, and homelessness.

The first in a two-part series on influential leaders who are reshaping Evangelical Christianity from within progressive and conservative circles. Jim Wallis founded “Sojourners” and now advises presidential candidates and world leaders in what he calls the “post-Religious Right” era. He is determined to put poverty at the top of America’s “moral values” agenda.

U.S. culture’s clash between religion and science is almost exclusively driven by Christian instincts and arguments. Hindu physicist V.V. Raman offers another view of religion, the universe, and the complementarity of the questions of science and faith.

The sales are starting, the stores are open late, and many of us are gearing up to spend more money than we actually have in a holiday season with deep roots in religion. We explore the turmoil many of us experience with money in our day-to-day lives — and how we might work towards a moral and practical balance for ourselves and the next generation.

A look inside the spiritual culture of Burma, exploring the meaning of monks taking to the streets there in September, the way in which religion and military rule are intertwined, and how Buddhism remains a force in and beyond the current crisis.

We explore the ideas and present-day relevance of 20th century theologian Reinhold Niebuhr, an influential, boundary-crossing voice in American public life. Niebuhr created the term “Christian realism:” a middle path between religious idealism and arrogance. Exploring his wide appeal, three distinctive voices describe Niebuhr’s legacy and ask what insights he brings to the political and religious dynamics of the early 21st century.

In 1965, a young Harvard professor became the best-selling voice of secularism in America with his book The Secular City. He sees the old thinking in the “new atheism” of figures like Richard Dawkins and Christopher Hitchens. The either/or debates between religion and atheism, he says, obscure the truly interesting interplay between faith and other forms of knowledge that is unfolding today.

In over 50 years as a Benedictine nun, Sister Joan Chittister has emerged as a powerful and uncomfortable voice in Roman Catholicism and in global politics. If women were ordained in the Catholic Church in our lifetime, some say, Joan Chittister would be the first female bishop.

Author Anchee Min has won acclaim for her memoir of growing up in China under Mao Zedong. She’s also written several works of fiction in which she explores the human hunger to survive against extreme social brutality. In this conversation, Anchee Min tells us what she learned about the human spirit in the forced labor camp in which she spent her teenage years, and how she’s found healing in America.

A 30-year-old, Indian-American Muslim and former Rhodes Scholar is setting out to change the way young people relate to their own religious traditions and those of others. Al-Qaeda is the most effective youth program in the world, he says, and we neglect this work at our peril.