Category mistakes

In her book Why Fish Don’t Exist, Lulu Miller talks about the philosophical idea that abstract things – “like justice, nostalgia, infinity, love, or sin” – do not come into being until we invent a word for them. Only after we name them do they become real, and potentially powerful. “We can declare war, truce, bankruptcy, love, innocence, or guilt,” writes Miller, “and in so doing, change the course of people’s lives.”

She points out that some people take this concept further, applying it to objects. Although the thing we call a “chair” clearly consists of matter, “chair” is just a category we have invented, with no reality independent of the human imagination. If we stopped thinking and talking about chairs, they would essentially cease to exist. Yes, it’s tough to get your head around that; we are very attached to these useful categories. But Miller suggests we should remain skeptical about our habit of “carving up the world” with names, because the enterprise sometimes goes awry. She asks rhetorically, “Were ‘slaves’ subhuman creatures, unworthy of freedom? Were ‘witches’ deserving of the stake?”

The book is primarily about David Starr Jordan, a biologist who is credited with discovering (and naming) about a fifth of the fish species known to science today. Miller becomes fascinated by this historical figure partly because of the man’s seemingly boundless optimism and perseverance, even in the face of professional setbacks and personal losses.

As a professor of zoology at Indiana University, Jordan assembled thousands of fish specimens, only to have the entire collection, and much of his written work, destroyed by a fire at his lab in 1883. Undeterred, he got to work collecting new specimens, resolving henceforth to “publish at once” when he made discoveries.

Two years later, at the tender age of 34, he became president of the university. His reputation grew, and in 1891 he accepted a position as founding president of Stanford University at Palo Alto, California – a gig that afforded him plenty of money to travel the world gathering more specimens. But fate struck him hard again in 1906 when the San Francisco earthquake rocked the campus, smashing his jars of fish and scattering the labels that identified them. In the immediate aftermath of the quake, Jordan’s staff salvaged as many fish as they could and hosed them down with water until they could be re-preserved in ethanol and relabelled, with name tags stitched to them. It was, in Miller’s description, a desperate exercise in “existential triage.”

To the author, Jordan represents an approach to science driven by the desire to create order from chaos. She understands this impulse because in her own life she has fought against despair – a predisposition she traces to her childhood, when her father, a gleeful atheist, informed her that life is essentially meaningless and that human beings are of vanishingly small significance in the universe.

But her inquiry into Jordan’s ideas and motivations reveals contradiction rather than clarity. This great man of science believed in “animal pauperism” – the unsupported theory that species, including our own, can “degenerate” due to bad breeding. On speaking tours, he espoused the merits of eugenics – a project to weed out undesirable human traits – and he advocated sterilizing those deemed “unfit.”

Jordan was hardly alone in holding these views. Eugenics went mainstream in the early 20th century, infiltrating politics and academia. It was a key concept in The Passing of the Great Race, a pseudoscientific treatise on Nordic supremacy by the American anthropologist Madison Grant, which was published in 1916 and enthusiastically embraced by a young Adolph Hitler.

Some scientists rejected eugenics, reiterating Darwin’s statements on the importance of genetic variation and the unknowable potential value of any and all traits. But Jordan and other eugenicists persisted, helping to put the idea into practice well before the Nazis did. Thousands of people were forcibly sterilized in the U.S. (as in Canada and many other countries), including disproportionate numbers of immigrants, Black women, and First Nations people. “And, mind bogglingly, approximately a third of all Puerto Rican women were sterilized by the U.S. government between 1933 and 1968,” writes Miller.

The author berates herself for having once put Jordan on a pedestal. As it turns out, the famous ichthyologist was a deeply flawed scientist. He clung to the fallacy of a “ladder of Life,” a biological hierarchy waiting to be discovered in the natural world. “This was what Darwin was trying so hard to get his readers to see. There is no ladder,” writes Miller. “The rungs we see are figments of our imagination, more about ‘convenience’ than truth.”

This was borne out by a scientific shift that began in the 1980s when taxonomists came to the realization that “fish,” as a category, has no evolutionary basis. The numerous aquatic species we call by this name are wildly diverse; physiologically, some of them have more in common with certain terrestrial animals than with each other. In a sense, Jordan’s career was based on a delusion. The scientific framework that he assumed to be immutable was, in fact, a fiction.

Miller asks herself whether the existence of “fish” matters, or if it is mere semantics – just a “linguistic party trick.” In the end, she sees that it is an instance of reconsidering conventional truths, which is the very essence of scientific inquiry. There is always resistance to giving up old systems of belief – it took humanity a long time to let go of the comforting notion that the sun revolves around the Earth – but this is the only way to increase our understanding of the universe.

“What other truths are waiting behind the lines we draw over nature? What other categories are about to cave in?” she asks. “The longer we examine our world, the stranger it proves to be. Perhaps there will be a mother waiting inside a person deemed unfit. Perhaps there will be a medicine inside a weed. Salvation inside the kind of person you had discounted.”

This, she concludes, is the better way to fend off despair: embracing curiosity, rather than pursuing fixed goals and insisting on certainty. It also involves remembering that science is not truth itself, but “a blunt tool that can wreak a lot of havoc along the way.” Miller cites the faux science still espoused by 21st-century white supremacists. “This ladder,” she writes, “it is a dangerous fiction.”

Why Fish Don’t Exist is partly about reappraising public figures who were once venerated. There is always resistance, from those who say we should not judge long-dead people by today’s standards. But maybe the spirit of scientific inquiry is a useful guide here. Surely we can agree that history is not truth itself, but an active endeavour – an ongoing process of reappraisal. (Six months after the original publication of this book, both Stanford and Indiana U. renamed buildings that had been named after David Starr Jordan.)

I found the book thought-provoking, informative, and – thanks to a breezy writing style – highly entertaining. It has a distinct NPR podcast vibe, which is not surprising, since that is how the author built her career. The hallmark of this style is transparency – revealing the journalistic process (not just the facts, ma’am). I occasionally felt that the episodes from Miller’s personal life interwoven into the story – her struggles with mental health, with relationships, with work – were a bit jarring. Maybe this is a generational thing, and younger readers would be less concerned with categorizing the book as a memoir or as a work of popular science. In any case, I see the point. It’s a way of being upfront about your subjectivity, instead of pretending to be an objective observer – and this is highly relevant to the subject matter. DL