“Words belong to each other,” Virginia Woolf memorably proclaimed in the only surviving recording of her voice. But even in this beautifully aphoristic observation lies an unsolvable chicken-or-egg mystery: Where did words come from in the first place?

Charles Darwin — man of routine, graphic novel hero, upbeat evaluator of marriage, occasional grump, poetry muse, rap muse, frequent literary jukeboxer — may have carved his place in history as the father of evolutionary theory, but he also demonstrated that science and the humanities need each other as he made major contributions to our understanding of why language emerged and how it shaped the course of our species.

In The First Word: The Search for the Origins of Language (public library) — the fascinating chronicle of two intertwined stories, of how language evolved long ago and of what spurred a handful of modern scientists, including Darwin, to explore that mystery at the specific time they did — science writer Christine Kenneally traces Darwin’s linguistic legacy:

Although Darwin mentioned language very little in On the Origin of Species, the book is a keystone for every discussion about language evolution that has followed it. In fact, all debate about who we are and how we came to be on this planet can be divided into conversations that took place before the publication of Origin and those that have taken place after it. Origin was printed six times during Darwin’s lifetime, and many times since. Not only did it introduce the concept of evolution … but it initiated the modern study of evolutionary biology. The flow of books published about Darwin every year seems endless.

Darwin focused more on language in The Descent of Man (1871) than in Origin. Language was not a conscious invention, he said, but “it has been slowly and unconsciously developed by many steps.” At the same time, he noted, humans don’t speak unless they are taught to do so … because language is “not a true instinct.”

Darwin believed that language was half art, half instinct, and he made the case that using sound to express thoughts and be understood by others was not an activity unique to humans. He cited the examples of monkeys that uttered at least six different cries, of dogs that barked in four or five different tones, and of domesticated fowl that had “at least a dozen significant sounds.” He noted that parrots can sound exactly like humans and described a South American parrot that was the only living creature that could utter the words of an extinct tribe. Darwin included gesture and facial expressions under the rubric of language: “The movements of the features and gestures of monkeys are understood by us, and they partly understand ours.”

In fact, the father of evolution, known for his experiments on emotional expression in humans and animals, was also one of history’s most significant dog-lovers and, at a time when the question of what it means to be human stripped most other sentient beings of comprehension and cognition, he believed dogs were capable of both:

“As everyone knows,” he wrote, “dogs understand many words and sentences.” He likened them to small babies who comprehend a great deal of speech but can’t utter it themselves. Darwin quoted his fellow scholar Leslie Stephen: “A dog frames a general concept of cats or sheep, and knows the corresponding words as well as a philosopher [does].”

He also explored the question of why birds sing with a surprisingly humanistic lens:

Darwin also pointed out compelling parallels between human language and birdsong. All birds, like all humans, utter spontaneous cries of emotion that are very similar. And both also learn how to arrange sound in particular ways from their parents. “The instinctive tendency to acquire an art,” said Darwin, “is not peculiar to man.”

What set us apart from animals, he argued, was a matter of degree, not kind — a greater ability to produce sounds and ideas, an expression of our higher mental powers. Where humans differ from other animals, Darwin believed, is simply in our greater capacity to put together sounds with ideas, which is a function of our higher mental powers.

But as the era’s linguists enthusiastically embraced the perfect parallel biological evolution offered a for the emergence of language, they remained skeptical about how scientific a problem speculating about the origin of language was and were thus ambivalent about adopting Darwin’s theory as fact. Perhaps ironically, given we now know that ignorance is what drives rather than hinders science and Richard Feynman has wisely advised that allowing for uncertainty and doubt is scientists’ chief responsibility, this inability to remain speculative resulted in one of the most profound instances of censorship in scientific history:

The distaste for speculation about language origins culminated in an extraordinary move by the Société de Linguistique of Paris in the nineteenth century: it banned any discussion of the subject, even though it was attracting more and more attention. Its pronouncement read: “The Society will accept no communication concerning either the origin of language or the creation of a universal language.” In 1872 the London Philological Society followed suit.

This act of academic censorship, Kenneally writes, had strikingly enduring consequences. It wasn’t until nearly a century later that a handful of modern linguistic heroes — scientists like Noam Chomsky and Stephen Pinker — picked up the vetoed inquiry, and the rest, as they say, is history.

The First Word: The Search for the Origins of Language, which is spectacularly stimulating, goes on to explore the enduring mystery of how our vehicle of communication evolved. Kenneally frames the journey with precisely the blend of poetic reflection and rigorous scientific inquiry that underpins the fascinating story she unravels:

For all its power to wound and seduce, speech is our most ephemeral creation; it is little more than air. It exits the body as a series of puffs and dissipates quickly into the atmosphere.

[…]

Only very recently have scientists begun to work out how language evolved. But in the same way that no single fossil can provide an answer, no one researcher can solve this problem, which is fundamentally awesome and multifaceted. There will be no Einstein of linguistic evolution, no single grand theory of the emergence of language. Unearthing the earliest origins of words and sentences requires the combined knowledge of half a dozen different disciplines, hundreds of intelligent, dedicated researchers, and a handful of visionary individuals. Finding out how language started requires technology that was invented last week and experiments that were conducted yesterday. It also needs simple basic experiments that have never been done before.