That human society or even the human species might not survive was an idea not unfamiliar to ancient philosophers. Seneca the Younger, tutor of the emperor nero, observed:
The entire human race, both present and future, is condemned to death. All the cities that have ever held dominion or been the splendid jewels of empires—some day men will ask where they were. They will be swept away by various kinds of destruction: some will be ruined by wars, oth- ers will be destroyed by idleness and a peace that ends in sloth, or by luxury, the bane of those of great wealth. All these fertile plains will be blotted out of sight by a sudden overflowing of the sea, or the subsiding of the land will sweep them away suddenly into the abyss.
Among the civilization-ending disasters Seneca anticipates, some are anthropogenic and others have natural causes. Living at a time when his city was powerful and its empire still growing, his prediction was first and foremost intended as a moral censure of Rome. The idea that failings such as idleness and indulgence in luxury could endanger a society’s durability was a commonplace to which he gave new force. In the face of this dismal prediction, what could a person do? His answer is often quoted by modern writers: “enjoy present pleasures in such a way as not to injure future ones.”2 This maxim of hedonistic calculus is not adequate counsel for sustainability; for it to be that, it must be addressed to society rather than the individual, and “pleasure” must yield to “needs.”