"Optimism wars against restraint when it tells us that we can have it all, and when it tells us that values will always keep increasing, and that we can have the goods we seek more often and at less cost. Optimism wars against nature when it tells us that there will always be a technological or mechanistic fix to any jam in which we happen to find ourselves. As we are beginning to face a world where there are no longer problems to be solved so much as realities to be borne, a healthy move away from optimism is the first step towards finding some lasting happiness in a confused and fallen world."
I responded in the comments by saying that the day I read the article I was also reading Aeschylus' Prometheus Bound. The following passage struck me as relevant to what Larison was saying. The context is that Prometheus has been riveted to a mountain on orders from Zeus. The Chorus is questioning Prometheus about what his crime was.
Chorus: Did your offense perhaps go further than you have said?
Prometheus: Yes, I caused men no longer to foresee their death.
Chorus: What cure did you discover for their misery?
Prometheus: I planted firmly in their hearts blind hopefulness.
Chorus: Your gift brought them great blessing.
Prometheus: I did more than that; I gave them fire.
Chorus: What? Men, whose life is but a day, possess already the hot radiance of fire?
Prometheus: They do; and with it they shall master many crafts.
Chorus: This then was the offense for which you suffer here...
So I'm oversimplifying but Prometheus strikes me as a progressive, always hopeful for the future of a creative mankind. While Chorus seems to wonder why Prometheus would grant finite creatures such hope, in the form of fire, though their life is "but a day." I think Prometheus realizes it and that's why he calls it a blind hope. So Prometheus plays the part of the progressive while Zeus is the conservative. Of course he's conservative. He's in power after all. Thanks to the help of Prometheus in the "progressive" rebellion, he is now lord of the gods.