Review by SFI Professor C. Brandon Ogbunu
While “optimism” isn’t quite a taboo word in science, it is not a sentiment that most scientists would use to describe their outlook. So much of the process of science is defined by failure, and successes are caricatured as intrepid scientists raging against a status quo machine. The navigation of conflict and of triumph over non-believers are the conscious calling cards of many successful scientists.
In It Could Be Otherwise (Basic Books, 2026), neurobiologist and SFI Fractal Faculty Stuart Firestein proposes a subtly radical notion: that optimism, as much as conflict, has always been a character in the development of modern science, and that it should be named and clarified. Doing so, he argues, is not only consistent with the history of scientific progress but can lead to a more creative and integrative scientific endeavor, better equipped to study the natural world.
It Could be Otherwise serves as the rare rigorous-but-accessible take on the history and philosophy of science. Using his own research in these areas, Firestein explains how the notion of progress has been built, and that it requires a linear view of time, a belief in the notion that the universe is law-abiding, and a broad accessibility of ideas, such that their triumphs are appreciated by the public. This argument sets the table for the more provocative claim about how science has already carried a hidden positivist agenda: there is a historical arrow from ignorance to knowledge production, and optimism operates in these margins.
What then, is Firestein pushing back against? Not against pessimism, but against its close relative, determinism: the notion that the apparent caprice of natural systems can be neatly resolved into laws and axioms. He pulls no punches in his views on this. In Chapter 4, “F—— the Enlightenment” — a critical take on the Enlightenment’s attempt to compress complex natural phenomena into neat formalisms — he laments, “If everything is all worked out, inexorably proceeding like the ticks of a clock ever since the Big Bang…then what’s the point, really?” (p. 92)
Firestein offers this take while effectively walking the line between a scholarly story of the triumphs and (especially) perils of determinism, which shrinks the scientific imagination by assuming an overly simplified picture of the natural world.
He uses several case studies to illustrate these points. In Chapter 5, “Science Evolves,” he properly situates the legacy of Darwin as a triumph of the greater role of contingency in natural systems. This is an important point to emphasize: The triumph of Darwinism is not only about the specific mechanism for evolution, but about the grander message it communicated for how to study natural systems — with an appreciation for idiosyncrasy as a main feature of natural systems.
Firestein ventures into deeper waters in Chapter 8, “Complexity and Uncertainty.” Notably, he skillfully distinguishes terms which are often confounded: complexity, irreducible complexity, and uncertainty. Included in this is the proper positioning of determinism in this landscape, including the especially important caveat that determinism can co-exist with unpredictability. And he articulates what makes the triumphs of complexity science — chaos and emergence, for example — so subversive: they are perfectly consistent with our manner of conducting scientific research and provide rigorous formalisms, yet embrace the capriciousness of natural systems.
In the end, we are treated to a text that provides more than an introductory survey of the history of contemporary ideas. It is painted by Firestein’s warm and engaging writing style, which feels less like a pedantic lecture and more like a conversation. But none of this detracts from the seriousness of his thesis: whatever our disposition, science thrives on optimism. This is the reason we tolerate failed experiments, broken theories, and rejections from journals. To do science well and rigorously, we must believe that a better truth is possible.