Barry Kosmin is a sociologist, and is research professor in public policy and law at Trinity College. He is co-author of One Nation Under God and author of Religion in a Free Market. Kosmin was also the Principal investigator of the 2001 American Religious Identification Survey, the groundbreaking study on religion in America that showed the number of seculars in America has almost doubled in the ten years preceding the survey. In this discussion with D.J. Grothe, he details the scientific study of religion and secularism, the "secularization hypothesis," religious diversity in contemporary America, and the rise of the nonreligious in recent years. He also explores the relationship between science and secularism.