'For ours is a superior variant, and we are only just beginning. We are able to think-together ... we are not dogmatists teaching God how He should have ordered the world.
'The essential quality of life is living; the essential quality of living is change; change is evolution: and we are part of it.
'The static, the enemy of change, is the enemy of life, and therefore our implacable enemy. ..."
Wyndham, having lived in England through World War II, had a significant personal interest in the idea that people wrongly rely upon past concepts and cultural constructions to solve the problems of the present age and the projected problems of the near-future age. He was interested in presenting the idea that a new paradigm of thought--a casting off of the old and a groping for the new--was required to solve present and anticipated problems of society and culture and individuals' relationships with one another.
You can see Wyndham's dual interest in the ironic attitude the Lady from Sealand presents when she speaks of enmity with the Old People and demonstrates that enmity through destruction of the Old. The irony is that the ideas of enmity and destruction of enemies are the same paradigm that motivates Joseph Strorm and the whole Waknuk community.
Despite the irony of her position relating to enmity and destruction, Sealand Lady does reflect Wyndham's main message that change is inevitable and to resist change is to resist life (she does not speak for Wyndham with her emphasis on enmity and destruction). Sealand Lady does represent Wyndham's main message that a new way of thinking, a new paradigm of thought, is required to meet change.
No guarantees await them in the future. Sealand, ... is peopled by beings who ... [have] their obsession with Petra’s harrowing gift [and who] are doomed one day to self-destruct, [since they bear] the unyielding remnants of the Old People they are supplanting. (Magill’s, Salem Press on eNotes)
Sealand paradoxically (paradox: that which appears false but is true at the same time) represents both (1) the new way of thinking, which is the new paradigm solution to evolving life and evolving problems while also representing (2) what Wyndham believes to be the downfall of humanity: the urge to cling to old concepts and constructs, the old paradigm, when seeking and administering solutions to new problems, i.e., in Sealand, through enmity and destruction just like Joseph Strorm. In the case of The Chrysalids, the new problem is the mutation of "think-talk."