Recently Published Book Spotlight: Herald of a Restless World. How Henri Bergson Brought Philosophy to the People

This blog post is adapted from Emily Herring’s biography of Henri Bergson, Herald of a Restless World. How Henri Bergson Brought Philosophy to the People (Basic Books, 2024).

One day in the mid-1910s, as Henri Bergson was gathering his things after lecturing to a packed room at the Collège de France in Paris, a woman from the audience marched up to him. Without so much as an introduction, she demanded that he distill the essence of his philosophy in a few words. Bergson was irritated, and not just by the woman’s discourteous tone. In so many of his writings and lectures, he had returned to the idea that rigid concepts fail to convey the fluidity of reality. So to be put on the spot and forced to translate the nuances of his finespun developments into a punchy catchphrase felt nothing short of insulting. The woman did not seem to notice his annoyance and impatiently awaited his response.

With his characteristic dry wit disguised as smooth deference, Bergson replied, “I simply argue, Madam, that time is not space,” and without another word, he stood up and left. These four words deliver a concise but accurate characterization of durée, the central notion of Bergson’s philosophy. It was the idea to which he returned in all of his works, and the idea that made him famous.

We have no record of how Bergson arrived at durée, a complicated idea, arguably his most important one. In Bergson’s own telling, all of the doubts, questions, and ideas that had been bubbling up in the years since he left Paris had crystallized in Clermont-Ferrand in one fateful moment: “One day when I was explaining the sophisms of Zeno of Elea to my students on the blackboard, I began to see more clearly in which direction I should look.” We can imagine the lesson went something like this.

Outside the classroom window, thick, dark clouds in the distance gathered uninvitingly around the summits of extinct volcanoes. Bergson was still fairly inexperienced as a teacher, but his voice echoed impressively as he paced up and down the room. He spoke slowly, articulating carefully. His pauses were well-timed, and he never repeated himself. He unfolded long improvised sentences with remarkable precision, as though reading from a script.

“In the paradox of Achilles and the tortoise, the fastest runner never catches up to his slower opponent. In fact, according to Zeno, neither Achilles nor the tortoise will ever make it past the finish line.”

He turned to the blackboard and traced a long horizontal line.

“To run (or in the tortoise’s case, crawl) the distance separating the starting line from the finish line, one first has to cover half that distance.”

He drew an X at the line’s midpoint, separating it into two halves, then continued:

“But before getting to the halfway point, one needs to cover a quarter of the total distance, and before that, one- eighth of the total distance, and before that, one- sixteenth, and so on…”

He added several more Xs, dividing the line into shorter segments to represent a quarter, an eighth, and a sixteenth of its length.

“…such that neither can ever finish the race. In fact, neither can really ever take the first step, and therefore motion is a mere illusion. Or so Zeno claims.”

Bergson took a step back and gazed at the board. As he surveyed the crude diagram, a familiar feeling washed over him. An idea was germinating in his mind, pushing its way through the outer crust of his consciousness. Though not yet fully formed, the idea held the coloration and texture of something new and important. It contained the outlines of multiple new pathways suddenly opening up with the promise of all the exciting directions in which they might lead.

After class, Bergson continued to pull on the thread of his new idea. He exited the building, crossed the street, and walked among neat rows of trees, straight past his apartment building on boulevard Trudaine. Ten minutes later, he arrived at one of his favorite spots in Clermont-Ferrand, la Place d’Espagne. He knew that it had briefly been renamed Equality Square during the French Revolution, but later recovered its original name. Since then, it had remained an uneventful and quiet space he could visit when he needed to untie complicated theoretical knots. As he walked around the square, his new idea came more and more into focus. He could see vividly the gigantic, glaring flaw in Zeno’s cleverly crafted puzzle.

It was so obvious and simple that he could not believe no one else had spotted it yet.

That day, Bergson had been shocked to find that the scientific conception of time contained no temporality at all. It soon became clear to him that time as expressed by the letter “t” in the equations of mechanics in fact represented something quite different.

To theorize about time, scientists and mathematicians first had to stop it in its tracks. Something in constant flux, like time or movement, is difficult to talk about, to seize, and to measure. Scientific concepts and mathematical equations require stability. The many symbols and concepts we use to represent time and motion—minutes on a clock, pages on a calendar, points on a graph—are sophisticated ways of freezing time’s continuous flow, of cutting it up into identical, solid units in order to measure them. These units are positioned one after the other like objects in space, like interchangeable beads on a string.

This was particularly apparent in Zeno’s paradoxes. The Greek philosopher had intended to prove that the notions of movement and change hold an inherent contradiction. But as Bergson began to understand in front of the blackboard, these contradictions do not arise from movement itself, but from the ways in which we represent and spatialize movement. All Zeno had been able to show was that movement could be represented as a line, and that this line could be divided into as many points as the mathematician wanted. This is a useful way of grasping motion by immobilizing it, but it tells us little about how motion is experienced, or about the temporality of time.

In Zeno’s picture, Achilles’s majestic strides are chopped into tiny pieces, mutilated, until nothing is left. The hero stumbles and twitches, eternally convulsing on the spot. But that is not how people really move. When we leap, run, or dance, when we throw our hands up in the air in frustration, there is no halfway point. There is only movement, fluid and whole.

Previously, Bergson had claimed that he had no interest in psychology, but his discovery forced him to take a closer look at the mind. In a doctor’s waiting room an hour can feel like an eternity, but in the company of loved ones an hour seems to slip away before we even notice it was there. It is precisely this experience of the passing of time, the perceived difference in its quality, that is erased in the way science treats time. And it was this qualitative temporality that Bergson called durée.

What would happen, Bergson asked, if, through some magic spell, the earth completed a rotation on its own axis every twelve hours instead of every twenty-four? What if every other natural phenomenon accelerated proportionally? To the elaborate equations the astrophysicist devises to predict celestial phenomena this major shift in tempo would make no difference at all. The mathematical relations between the terms of the equations would not be impacted by the acceleration in pace; the proportions would remain intact. But for the astrophysicists themselves, for anyone who experiences temporality, a huge change would be perceived:

“Our consciousness would soon inform us of a shortening of the day if we had not experienced the usual amount of duration between sunrise and sunset. No doubt it would not measure this shortening, and perhaps it would not even perceive it immediately as a change of quantity; but it would realise in some way or another a decline in the usual storing up of experience, a change in the progress usually accomplished between sunrise and sunset.”

For Bergson, time is not an abstraction. It cannot be reduced to a symbolic notation. It is a real force acting in the world.

During his youth, Bergson had believed that science and philosophy are complementary because science is the form of knowledge that best grasps reality, while philosophy, in remaining at a certain degree of generality as it formulates all-embracing principles, is always somewhat removed from reality. But at some point in the early 1880s, through his careful analysis of the scientific notion of time, Bergson realized that it is science that provides a distorted picture of reality.

To measure or even talk about time and movement, science has to borrow from space, a category external to time, thus confusing time with space, movement with immobility. In realizing that philosophy, if conducted correctly, is in a position to capture the true, mobile essence of reality, Bergson relegated science to a useful but general and disconnected form of knowledge. This change of heart—Bergson’s discovery of durée—would resound throughout every theory he would ever formulate and forever transform Western thought.