Re: Try that with mythology (aka Religion)
But Religion does move forward, though some more quickly than others...
When most Western Atheist talk about Religion they often mean the Roman Catholic Church (RCC) which is just one of many branches of Christianity, let alone the religious sphere and happens to be one of the most dogmatic main branch of Christianity.
When you compare the RCC to (for example) some branches of the Anglican Church it becomes rather stunning how much faster the latter moves with the modern times. The Anglican Church is having an ongoing public debate about the acceptance of woman bishops (which some now have) and openly gay priests/bishops. Some moving allot quicker than others.
What we have is the movement of institutions rather than ideas. Throughout history whether it be the Scientific body or Religious believing in theory x (such as the existence of Aether or the static state model of the cosmos) have only moved forward when the group which holds the contrary theory outnumber the people who hold the original (usually through the death of the latter) and not, as most zealous Scientists would argue, though experimentation and logic (though this does help produce the opposition group).
What happens in religion is that the various churches split over theological points (see the split in the Eastern and Western Branches of Christianity over the argument over the nature of the Divinity of Jesus [water/wine water/oil debate]) whereas Science does not tend to so openly.
Yours sincerely
A Devout Agnostic who has spent years debunking the Bible to "believers"