– Just in time for Christmas ... a giant New Jersey billboard is challenging the existence of God. "You know it's a myth," says the atheist ad that appears over the entrance to the Lincoln Tunnel, featuring an image of the Magi traveling to a nativity scene. "This season, celebrate reason." The debate, of course, isn't ending there. A Catholic group has erected its own billboard on the Manhattan entrance to the tunnel reading: "You know it's real" over pictures of Mary and Joseph. "We can't enjoy the Christmas season without someone trying to dumb it down or neuter it," the president of the Catholic League told AP. Reps from American Atheists say they don't intend to offend anyone. They merely want to "encourage" other atheists to "come out of their closet to attack the myth that Christianity owns the solstice system," they said on their blog site. Each billboard cost close to $20,000.