No, Manichaeanism is definitely not dead. Reading Jane Jacobs’ Systems of Survival has convinced me that it is alive and thriving.
Terry’s manichaeanist remark is made a bit offhand, but it’s no throwaway point. The manichaeanist controversy, or heresy?depending on your perspective?has been going on literally for millennia, and it absolutely affects how people think and behave.
As a counterpoint, G.K. Chesterton’s book Thomas Aquinas: the Dumb Ox has a pretty approachable discussion of what’s all wrong with Manichaeanist thinking, and its implications. Better yet, the Chesterton discussion doesn’t require first-hand reading (thank you) of Summa Theologica or the entire Thomist catalog.
Not so good on markets, Chesterton, but very good on this stuff.