“Sentiment without action is the ruin of the soul.” -In Beyond the Wall, Abbey writes,

He began with an apocalyptic vision. “We’ll be here on a sand dune with Norwegian rats and cockroaches,” he told me, beginning eye contact that rarely broke for the next hour. “Those seem to be the creatures that can survive, which isn’t ideal.” - Douglas Tompkins founder of Esprit and The North Face*

Patagonia

Again this idea of progress and the effects of it.  I am sort of obsessed with this notion that there are too many people consuming too many resources.  Yet until it is too late I do not believe anything will be dealt with.  Reminds me of a line from Camus' "The Plague"

“In this respect, our townsfolk were like everybody else, wrapped up in themselves; in other words, they were humanists: they disbelieved in pestilences. A pestilence isn't a thing made to man's measure; therefore we tell ourselves that pestilence is a mere bogy of the mind, a bad dream that will pass away. But it doesn't always pass away and, from one bad dream to another, it is men who pass away, and the humanists first of all, because they have taken no precautions.” 
― Albert Camus, The Plague 

I like this one too

“There have been as many plagues as wars in history; yet always plagues and wars take people equally by surprise.” 
― Albert Camus, The Plague

“We’re not believers in the myth of progress,” he continued, his lecture unfolding without pause. “This requires systemic analysis and gives us an entirely different view of development. It’s common sense that the world has gone awfully wrong. We need a major rethink of what development means.” -* 

• humans have no right to reduce the richness and diversity of life forms except to satisfy emphatically vital needs. 
• They state that the human population must decrease for the well-being and flourishing of the nonhuman world. 
• They also state the need for a shift in basic economic, technological, and ideological structures in order to reduce the human interference in the nonhuman world. 
•  The final principle states that “those who subscribe to the foregoing points have an obligation directly or indirectly to try to implement the necessary changes.” --the beliefs of deep ecology by Naess and Sessions - *

*more here