Question the sanity of perpetual growth.
The picture below should make it clear that our planet is subject to physical limits. Although this is obvious at first glance, fringe economists like the late Julian Simon have convinced some people that a finite world can support infinite growth. We are told that the human mind is the "ultimate resource" and that Man is free from the physical constraints of the Earth's crust. Such infinite-abundance theories defy common sense and promote wasteful behavior. These superficially-appealing fantasies must be challenged until everyone is dealing with reality.
* Historical proof of what happens when limits are ignored
An easily accessible debunking of growthism can be found in the videotaped lectures of physicist Albert Bartlett. Search websites like YouTube and Google Video for his name. He covers topics ranging from naive city planning to peak oil production, and the flawed forecasts of people who don't grasp mathematics. Dr. Bartlett says "the greatest shortcoming of the human race is our inability to understand the exponential function."