Bait and Switch
First, we are told to save the Earth for posterity then the sort of philosophers who give the field a bad name tell us not to have posterity. (Philosophy isn't all pointless bullbleep; some of it is harmful bullbleep.) This is right up there with first telling us to use self-actualization and then telling us there is no self to actualize.
Note to philosophers: In That Hideous Strength by C. S. Lewis, Frost was not the hero.