It was probably a slip of the tongue. Last night, atheist Zachary Bos pounded his table at Aneka Rasa in Allston and shouted, "Oh my Lord!"

He quickly corrected himself.

"See? It's really offensive to use these religious epithets," he said.

Bos is the organizer of the Boston Atheists, an affiliate of American Atheists. He is a strict practitioner. He doesn't thank God for anything ("What about 'thank goodness'?" he quips), and he believes that atheists should have their own congregational group where they can affirm their beliefs. His goal is to provide Boston's atheists with the kind of social environment that other people get from churches -- from bingo nights to youth groups.

"What's nice about church is it's a social institution, and that's why people go to them," explained atheist Scott Gray.

The Boston Atheists have been planning social events through their Meet-up since 2002. The group gathers monthly at places like Aneka Rasa for drinks, dinner, and conversation. And to build a community. It's a necessary first step before the Atheists embark on what Bos calls the "congregational stage." That's when they get the bake sales.

It's not the sort of thing that develops overnight. Part of the challenge is organizing the kind of congregation that people would want to attend. That's why these monthly gatherings are so important.

"We're still trying to figure out what sorts of things we should do," said atheist Nora Delaney. "We're in a conversation stage where we are talking about building our community."

Bos admits that not everyone comes to the Meet-ups in the hopes of building a congregation. He says that organizing atheists is like "herding cats." And members mostly just want to chat.

"First and foremost, it's an event to get together with likeminded people," Bos explained. It's a place to have conversation about the intellectual pursuits, like cognitive science, computer programming, and philosophy, that group members share in common. But it also has a more prosaic role.

"I have the ambition to develop an atheist dating service," said Bos. "People marry within a church; where do atheists go to marry?"

Atheist David Schneider-Joseph is one member who thinks the idea of a formal atheist congregation is silly. For one thing, atheists are a diverse group.

"We're here because we're all atheists, but that doesn't say anything about our moral views," he said.

Schneider-Joseph was raised Catholic within a mixed marriage (his mother is Jewish) and he cites growing up with two faiths in the house as a factor in his early conversion -- at the age of seven. Nonetheless, he argues that atheism should be self-evident to everyone, eventually.

"It does not take a lot of genius to decide that a magical creator of the universe is absurd," he said. "If one is not coerced by fear, any modern person should come to the same conclusion."

He comes to the Meet-ups to be around people with a similar belief in science. "Atheists are a very diverse group of people who have something in common in terms of a unique approach, a skeptical way of viewing the world, and it's nice to be around that."

His skepticism is what leads him to distrust the idea of an atheist congregation. But he admits that his curiosity would probably get the better of him. "I'd probably check it out," he said.

Andrew Baughns, who was raised by strict Pentecostals, admits to being obsessed by religion.

"I'm interested in the religious mind-set, to what attracts people to religion. Thinking about what brings people to a religion is almost like a spectacle, like a sport," he said. Baughns views the religious as "trapped" and takes pride in the fact that he escaped.

"Take Pentecostals," he explained. "They set themselves apart from 'the world' because they forgo certain vices that they profess, at least, not to partake in. On the other hand, they partake in certain kinds of vices -- things that I consider vices -- homophobia -- and it's an indulgence, a ruse. They have a superiority complex, almost like they are using religion for feeling better than other people."

Baughns admits that he uses his atheism to a similar end, to feel better than other people. But, he insisted, his view is different.

"I don't have an image of what is perfect. I don't have to lie to myself when people present reality and facts. I don't have to run away ... Atheists are sort of forced to face the world as it is," he said.

Baughn, a short man with closely cropped black hair and square plastic glasses, has thought a lot about atheism and its personal implications. He said that his conversion experience was sort of like a phase transition in science. Just as water is a liquid until a certain threshold when it freezes into a solid, Baughn's faith turned to nonbelief at a certain threshold of scientific knowledge.

"Did you ever do the God test?" asked Ilya Zlatkovsky, an atheist with short, straight black hair and a long jaw that gives him a certain advantage when telling jokes. The God test, he explained, is when doubting children ask God to do a certain thing in exchange for faith. "I tried to get him to do my homework for me," Zlatkovsky explained.

The power that God can and cannot exert is something that is fundamental to Bos's vision of atheism. For example, Sonny Perdue, the governor of Georgia, recently held a service on the steps of the state capitol to plead for divine intervention in the statewide drought. That, to Bos, is dangerous.

"It's an important civic concern," Bos explained. "All of us are in the public sphere and we have to agree on the same tests of truth. Right now, we have different tests of truth." Some religious people, for example, believe that their governor can make God make it rain. Most of us leave that work to nimbus clouds -- or, in certain circumstances, Fat Joe and Lil' Wayne.

"I do think the world needs more atheists," agreed Sarah Trachtenberg, an atheist since nine years old.

The influence that religion exerts in the public sphere troubles many of the atheists in the group. But that doesn't mean that they want to drop out of society. In December, for example, they are going to a screening of The Golden Compass specifically because the Catholic League has called on people to boycott the film.

Indeed, as the meeting wound down last night, members were talking about their plans for Thanksgiving. (Zlatkovsky wants to do the turducken one better -- add a quail.) But, isn't the holiday about giving thanks to God?

"The first Thanksgiving was a European harvest festival where they shot their guns in the air," said Bos. "I'm going back to the fundamentalist roots of Thanksgiving."