Laissez-faire, laissez-passer

Laissez-faire, laissez-passer is presented as the slogan of a hands-off approach to nature, then challenged by Vera as an evasion of human responsibility. Its force in the novel comes from the clash between a call to let natural processes run unchecked and the recognition that human beings are themselves part of nature and can alter its course.

The slogan at the congress

At a scientific congress, an American advocate of biological liberalism argues that there is no longer any purpose in preventing animal and plant species from migrating. Nature, he says, should be left to sort things out, as it always has. The narrator recounts this exchange in a letter to Vera, recalling that she had supported his position when the argument began.

The maxim Laissez-faire, laissez-passer—rendered in the account as “Laissez faire, laissez passer”—condenses the advocate’s case into a principle of non-intervention: allow nature to act without human restraint. In this context, it is not an abstract political motto but a proposal about species movement and the management of ecological boundaries.

Vera’s rebuttal

Vera answers that human beings are nature too, and therefore cannot treat themselves as outsiders who may simply defer to an impersonal natural process. She argues that the congressman has misunderstood the narrator’s presentation and suggests that he should repeat his high-school ecology course. Her pointed formulation is that humanity has suspended natural selection.

She supports the distinction with a historical contrast: neither in the Jurassic nor in the Cretaceous were there intercontinental flights or even communication by ship between Gondwana and Laurasia. The modern movement of species across those distances is therefore not equivalent to the slower processes of earlier geological eras. When the advocate responds, “Laissez faire, laissez passer,” the repeated slogan functions as a refusal to engage with the difference Vera has identified, rather than as an answer to it.

Ecological and narrative significance

The exchange places responsibility, not simply restraint, at the center of the dispute. The advocate treats non-intervention as though it restored nature’s own order; Vera’s reply insists that human agency is already embedded in nature and that contemporary ecological conditions cannot be separated from it. Her argument does not erase the distinction between human action and natural processes. Instead, it challenges the assumption that doing nothing is neutral when people have changed the conditions under which those processes operate.

The episode also joins scientific debate to the narrator’s personal history. Vera’s defense of his presentation becomes a public sign of their intellectual solidarity only months after their separation. Because other attendees know they were married, the narrator says they take care not to be seen together too often, lest their closeness invite gossip or speculation about the accident. The motto thus appears within both an ecological argument about intervention and a carefully managed reunion in which the former spouses support one another while keeping their distance.