As one of the nation's foremost skeptics, Michael Shermer's days as a born-again Christian might seem like another lifetime to him.

AMHERST, N.Y. -- With construction vehicles rumbling outside the window, Paul Kurtz said he had been assured work on his expanding offices would be complete in 48 hours.

"I don't believe in miracles _ at all, but ..." he smiled.

An understatement if ever there was one.

Kurtz has made it his life's work to promote reason over religion, science over silliness.

On Thursday, the pre-eminent skeptic welcomed hundreds of scientists, academics and authors to a thinking person's conference at the Center for Inquiry he founded.

The Tenth World Congress, "Toward a New Enlightenment," was to respond to assaults on free inquiry that participants said threaten advances not only in science and medicine, but democracy itself.

"We are disturbed by the growth of antiscientific attitudes in the world, and particularly in the United States," Kurtz said.

He pointed to religious-based objections to stem-cell research and the economic- and political-driven denial of global warming despite evidence to support it.

For three days, participants planned to explore issues such as physician-assisted suicide, evolution and ethics through the lens of science.

"Unfortunately," Kurtz said, "too many well-meaning people base their conceptions of the universe on ancient books, such as the Quran and the Bible, rather than going directly to the book of nature."

The congress coincides with the 25th anniversary of the Council for Secular Humanism, the arm of the center dedicated to promoting a nonreligious philosophy.

Conference participants include Richard Dawkins, an Oxford University evolutionary biologist famed for saying Darwinian evolution excludes belief in God, and philosopher Antony Flew, who made waves when he recently acknowledged second thoughts about the atheistic views he has promoted for 50 years. Flew said biologists' findings on the complexity of the DNA encoded in each cell pointed at least to the possibility that "intelligence" could be involved.

Other speakers include Nobel Prize laureates Sir Herman Kroto and Herbert Hauptmann, and Etienne-Emile Baulieu, who discovered RU486, the "morning-after pill."

As the conference opened, Edward Tabash, chair of the center's First Amendment Task Force, spoke of "a perversion" in society where those who blindly follow conventional religion are held in higher moral esteem that those who "follow the evidence where it leads" and challenge it.

"The ultimate objective I think we should all strive for," Tabash said, "is an America in which no one's liberty depends in any way on their either accepting or rejecting any religious belief system."

The 13-year-old Center for Inquiry has long worked to debunk claims of the paranormal and urban legends, the stories of the Virgin Mary appearing on grilled cheese or aliens arriving in spaceships.

With its $2.5 million expansion, the center is determined to put science _ and an appreciation of the methods of science _ front and center in America, concerned the country is falling behind.

"The cultivation of critical thinking is essential not only for science but for an educated citizenry, especially if democracy is to flourish," Kurtz said.

The Center for Inquiry has 18 chapters around the world and publishes 17 magazines dedicated to critical thinking, intellectual freedom and the scientific outlook.

The Cincinnati Skeptics Society is more than just a group that challenges claims of UFOs and psychic phenomena. The group also discusses political issues, literature and current events.

For a self-proclaimed skeptic who decries many religious beliefs as simply dumb, humorist-author Steve Allen shows up as a welcome figure in a surprising number of tabernacles.