Freethought Day commemorates an Oct. 12, 1692, evidentiary decision by William Phipps, governor of the Colony of Massachusetts, that ended the Salem witch trials. An outdoor observance marking the anniversary is held each year in Sacramento, Calif.

Frank Palumbo is a professor and director of the Center on Drugs and Public Policy at the University of Maryland School of Pharmacy in Baltimore.

Read an article on CNN about Blasphemy Day. Blasphemy Day was first officially observed on Sept. 30, 2009. Dedicated to the premise of free expression, the inaugural event featured lectures, provocative exhibits and other activities in a number of North American cities. The Center for Inquiry recently changed the name of the observance to International Blasphemy […]

The Association of Religion Data Archives posts data about Americans’ belief in God (from a 2007 Baylor University study).

The Association of Religion Data Archives posts data (from the 2005 World Christian Database) about atheism worldwide, broken down by region and country.

Adherents.com posts lists of the countries with the highest proportion and highest numbers of atheists and agnostics in 2005.

About.com cites a number of polls on Americans’ attitudes toward atheists.

A Barna study, conducted from January 2007 through January 2008, found similar percentages for divorce among atheists and agnostics as among Christians. The Barna Group partners with organizations and others “to be a catalyst in moral, social, and spiritual transformation.”

Read about a survey of atheists, agnostics and Christians conducted by the Barna Group from January 2005 through January 2007. The findings compare the groups’ attitudes and behaviors on matters ranging from political involvement to charitable contributions and volunteerism.