Some people view life spreading off the earth as an "infection" that should be avoided. Others see anything other than filling the galaxy with as much life as possible as immoral. Some people think it is morally necessary to have policies such as a 'prime directive' outlawing intervention of any non human or non earth life systems, while others think quite differently. Is the milky way galaxy a 'pristine canvas' being contaminated by life from earth?
An article published in The Daily Galaxy
entitled "The Earth Strain"
discusses the issue of whether or not we want to be spreading life to the stars.
The goal of this topic is a concise survey of all the various points of view, and associated rational for such, along with a quantitative survey of who believes what.