“The quality of a civilisation,” Iris Murdoch insisted in her sublimely insightful “Salvation by Words,” “depends upon the scope and purity of its language.” Two decades later, in becoming the first black woman to receive the Nobel Prize in Literature, Toni Morrison bellowed elemental truth from the Stockholm podium in her remarkable acceptance speech: “We die. That may be the meaning of life. But we do language. That may be the measure of our lives.”

More than a century before Murdoch and Morrison, long before the field now known as psycholinguistics existed, another great mind examined the role of language in what makes us human at the most fundamental level of our evolutionary biology — a concept itself then brand new and ferociously disputed.

Practically self-taught, the 19th-century English biologist and comparative anatomist Thomas Henry Huxley (May 4, 1825–June 29, 1895) helped pioneer scientific education in Great Britain, crusaded against religious extremism, coined the term agnosticism, and became the fiercest public champion of Darwin’s then-controversial theory of evolution, beginning with a praiseful anonymous review when On the Origin of Species was published in 1859 and culminating with a series of six laudatory public lectures he delivered the following year as part of the wonderfully titled “Lectures to Working Men” at the Museum of Practical Geology, now part of London’s iconic Natural History Museum. They were eventually included in Huxley’s essay collection Man’s Place in Nature (free ebook | public library).

In the final lecture, extolling Darwin’s epoch-making contribution to science and our understanding of nature — a contribution the full scope and impact of which Huxley would not live to see — he draws out the elemental question of what makes us human:

What is it that constitutes and makes man what he is? What is it but his power of language — that language giving him the means of recording his experience — making every generation somewhat wiser than its predecessor, — more in accordance with the established order of the universe?

What is it but this power of speech, of recording experience, which enables men to be men — looking before and after and, in some dim sense, understanding the working of this wondrous universe — and which distinguishes man from the whole of the brute world? I say that this functional difference is vast, unfathomable, and truly infinite in its consequences; and I say at the same time, that it may depend upon structural differences which shall be absolutely inappreciable to us with our present means of investigation.

A century and a half before Ursula K. Le Guin observed that “words are events, they do things, change things… feed energy back and forth and amplify it,” and long before the birth of neuroscience, Huxley considers the nature of speech itself — a phenomenon entwining our physiology and our psychology more intricately than any other:

I am speaking to you at this moment, but if you were to alter, in the minutest degree, the proportion of the nervous forces now active in the two nerves which supply the muscles of my glottis, I should become suddenly dumb. The voice is produced only so long as the vocal chords are parallel; and these are parallel only so long as certain muscles contract with exact equality; and that again depends on the equality of action of those two nerves I spoke of. So that a change of the minutest kind in the structure of one of these nerves, or in the structure of the part in which it originates, or of the supply of blood to that part, or of one of the muscles to which it is distributed, might render all of us dumb. But a race of dumb men, deprived of all communication with those who could speak, would be little indeed removed from the brutes. And the moral and intellectual difference between them and ourselves would be practically infinite, though the naturalist should not be able to find a single shadow of even specific structural difference.

In other words — for words, after all, are all we have in making sense and navigating meaning — Virginia Woolf was right in writing that “communication is health; communication is truth; communication is happiness.” Communication is, above all, humanity. But it was Darwin who moored this ancient intuition of artists and poets alike to the facts of science, effecting a larger truth about who and what we are.

Couple with Nietzsche on how we use language to both reveal and conceal reality, then revisit Darwin’s touching letter of gratitude to his best friend, who had supported him and defended him against the towering tides of convention with which his theory of evolution was met.