The Irony of Moving Backward to the Future
The proposed response of Dr. Kierans to the ever-encroaching jungle and deterioration of civilization as they know it is to embrace humanity’s supposed slow descent into their primitive, pre-historic condition. He effectively proposes that for humanity to adapt to the new “normal” they must discard all the achievements mankind has attained over the millennia in order to more effectively move forward into this new era--moving backward to the future--in a manner of speaking.
The Irony of Civilization
The representatives of last vestiges of civilization are far from being truly civilized. Beatrice Dahl is a decadent, lazy, rich girl--possibly the last of her kind and the last of humanity with access to such luxuries--yet she does nothing to help human civilization survive or flourish, choosing instead to live out her days lounging in the pool in a bikini getting drunk. Strangeman has access to old, functional tech but rather than work to help the rest of the survivors out he works to establish his own little cult of devotees.
The Irony of Man’s Superiority
Man’s superiority ultimately is built upon a single premise: favorable weather. Remove this condition and man is reduced to an animal. This is very strange turn of events considering that there are some prehistoric cultures that have emerged from tropical climates that have been able to carve out a considerably advanced society.
The Irony of Science
Science, at least in the novel, is a joke. The scientists tasked to do research gather data that serves to prove what was already predicted some decades earlier rather than discover anything that would propel humanity to the future or create solutions for current problems faced.
The Irony of a Solution
Dr. Kierans' proposal--effectively throwing all of man’s achievements out the window--primarily involves devolving into a chest-thumping primate as a means of embracing all of the changes affecting the globe. This is not so much a solution as giving up the fight and conceding to nature. Ironic given that man’s history is a chronicle of exactly that, rising above constraints put forth by nature.