Calgary Transit buses could soon be sporting advertisements questioning the existence of God.

The Freethought Association of Canada, which isco-ordinating the Canadian Atheist Bus Campaign, says Calgary will follow Toronto as the next city where it hopes to buy ads on public transit.

Atheist organizations have already launched transit ad campaigns in London, Madrid and Washington, D. C.,using the message, "There's probably no God. Now stop worrying and enjoy your life."

Justin Trottier, president of the Toronto-based Freethought Association, said Calgarians have been major contributors to the campaign, which he says has raised close to $30,000 across Canada.

"About half our donations have come from outside Ontario, with a lot of response from Calgary and Halifax," said Trottier.

Trottier said the slogan has run on London buses, gaining worldwide attention, and is the result of a compromise between atheists and authorities, so he's hoping Canadian agencies will approve it, too.

Calgary Transit spokesman Ron Collins said as long as the content complies with the criteria set out by the Advertising Standards Canada agency, the ads would be permitted.

"We know not everyone is going to be accepting of this. We know we're going to receive complaints, but it gets back to explaining to people the process of how they would meet the standards," said Collins.

Calgary Catholic Bishop Fred Henry said the ideal date to launch such a campaign would be April Fool's Day.

"I don't know what the norms Calgary Transit uses to accept advertising, but if the benchmark is that it should be non-offensive, I'm offended," said Henry.

"This is insulting to us. The interfaith dialogue that goes on in this city is characterized by deep respect for all the individual players."

Henry characterized the ad's message as aggressive, inward-looking, self-indulgent and narcissistic.

ads that say, "there's probably no god. now stop worrying and enjoy your life," could soon be on city buses.

"Right now there seems to be an attempt to marginalize Christians. The promoters of this say they want a fruitful dialogue, but I think we know better," said Henry.

Terry Young, senior pastor of First Alliance, one of Calgary's largest churches, predicts a range of reactions to the ads.

"It definitely represents a counterpoint to what a lot of people believe," said Young.

"You are going to have some people who will be offended by it and others who will acknowledge that that perspective is out there in the pluralistic world we live in," Young said.

Cliff Erasmus, executive chairman of the Calgary Centre For Inquiry, said the local atheist group is still working out final details of the ad campaign.

"We need it here badly. I'm very happy to see that humanists, atheists and agnostics are feeling it's safe to come out and talk about this," said Erasmus.

"I really want to have a dialogue with the people of faith in this community and show them we're not a bunch of hate-mongers. We're all here to share this planet together."