If you stare into the Abyss long enough the Abyss stares back at you.
When you look into an abyss, the abyss also looks into you.
When you gaze long into the Abyss of Sustainability, the Abyss of Sustainability also gazes into you.
And if you are not a bird, then beware of coming to rest above an abyss.
When you stare into an abyss for a long time, the abyss also stares into you.