Bergson: The Philosophy of 'Duration' — Why Lived Time Escapes the Grasp of Science

Key Takeaways

• Duration (durée): Bergson drew a sharp distinction between the homogeneous time measured by clocks and the qualitative, continuous time lived within consciousness (durée). This distinction reveals a layer of human experience that science alone cannot capture, and connects directly to contemporary research on consciousness and time perception.
• Intuition and intellect: The intellect divides and fixes the world in order to grasp it, but cannot capture the fluidity of reality as it is. Intuition, Bergson argued, is the method that makes direct contact with duration. This was not anti-intellectualism but an attempt to establish a method unique to philosophy, grounded in a clear-eyed assessment of what the intellect can and cannot do.
• Élan vital (vital impetus): Evolution is neither the mechanical accumulation of adaptations nor convergence toward a predetermined goal. The bold hypothesis that an "élan vital" — essentially unpredictable in its creativity — drives evolution remains a philosophical challenge to biological reductionism.

Life and Historical Context

Henri Bergson was born in Paris on October 18, 1859. His father Michel was a Polish-Jewish musician; his mother Katherine was of English-Jewish descent. After spending part of his early childhood in London, he returned to Paris at the age of nine and enrolled in the prestigious Lycée Condorcet.

The young Bergson showed exceptional talent in mathematics, winning a prize at the national Concours Général. Everyone urged him toward the sciences, but he chose philosophy instead. His math teacher reportedly lamented that he had "betrayed mathematics." Yet this choice was no accident. Having sensed from within mathematics the limits of mathematical thinking, he was drawn to what would become his lifelong theme: the limits of the intellect.

In 1878, he entered the École Normale Supérieure, where his classmates included the sociologist Émile Durkheim and the politician Jean Jaurès. French philosophy at the time was dominated by two currents: Spencer's evolutionary positivism and Kantianism. As a young man, Bergson was drawn to Spencer, but he soon noticed the shallowness of Spencer's concept of time. Spencer spoke of "evolution" without ever taking time seriously. This realization became the starting point of Bergson's philosophy.

After passing the agrégation in philosophy in 1881, he taught at provincial lycées — first in Angers, then in Clermont-Ferrand — while completing his first major work, the Essay on the Immediate Data of Consciousness (1889), as his doctoral thesis. In this book he systematically introduced the concept of "duration" and fundamentally reframed the problem of determinism and free will in psychology.

In 1900, Bergson was appointed professor at the Collège de France. His lectures became a Parisian sensation. The lecture hall overflowed not only with students but with society ladies, artists, and intellectuals from abroad, even causing traffic jams. William James traveled to Paris expressly to hear him and was deeply impressed; T.S. Eliot was among the audience as well.

With Creative Evolution in 1907, Bergson's fame reached its zenith. During World War I, the French government sent him to the United States as a secret envoy (1917), and he is said to have influenced President Wilson's decision to enter the war. After the war, he served as the first president of the International Commission on Intellectual Cooperation, a precursor to UNESCO. In 1927, he was awarded the Nobel Prize in Literature — an exceptionally rare honor for a philosopher, bestowed in recognition of the beauty of his prose.

His later years, however, were marked by suffering. Crippled by severe rheumatoid arthritis, he became nearly immobile. In 1940, the Vichy government of Nazi-occupied France enacted anti-Jewish legislation. Despite his fame, which would have made an exemption possible, Bergson refused it. Though he had grown deeply sympathetic to Catholicism in his final years, he chose to remain alongside the persecuted Jewish community. His will reads: "I would have converted, had I not seen the great wave of anti-Semitism rising in the world. I wished to remain among those who tomorrow would be persecuted."

On January 4, 1941, Bergson died in occupied Paris at the age of eighty-one. The funeral was a modest affair. The philosopher who had once commanded the greatest intellectual fame in Europe passed from the world almost forgotten.

Timeline

• 1859: Born in Paris (father: Polish-Jewish musician; mother: English-Jewish)
• 1878: Enters the École Normale Supérieure
• 1881: Passes the agrégation in philosophy; begins teaching at provincial lycées
• 1889: Publishes Time and Free Will (doctoral thesis)
• 1896: Publishes Matter and Memory
• 1900: Appointed professor at the Collège de France; publishes Laughter
• 1907: Publishes Creative Evolution; international fame reaches its peak
• 1914: Elected to the Académie française
• 1917: Visits the United States as a French government envoy
• 1922: Debate with Einstein on the nature of time; publishes Duration and Simultaneity
• 1927: Awarded the Nobel Prize in Literature
• 1932: Publishes his final major work, The Two Sources of Morality and Religion
• 1940: Refuses exemption from the Vichy government's anti-Jewish laws
• 1941: Dies in occupied Paris (aged 81)

What Did Bergson Ask?

In the second half of the nineteenth century, science was enjoying overwhelming success. Newtonian mechanics predicted the motions of celestial bodies, thermodynamics powered steam engines, and Darwin's theory of evolution explained the origin of life through natural law. As an extension of these triumphs, there grew a widespread conviction that even human consciousness could be explained by physical and physiological laws.

Gustav Fechner, the founder of psychophysics, claimed that the intensity of sensations could be measured mathematically. Bergson challenged this assumption head-on. What does it even mean for sadness to "double"? Can the "magnitude" of joy be compared numerically? Behind every attempt to treat emotions and consciousness quantitatively, a hidden premise lurks: the assumption that everything can be reduced to spatial quantity. Bergson saw through it.

From this insight his fundamental question was born: Is the "spatialized time" that science presupposes really the same thing as the "time" actually lived within consciousness?

This question is less naive than it may appear. If these two kinds of "time" are fundamentally different, then science captures only one aspect of reality. Understanding consciousness, freedom, life, and creativity would require a method peculiar to philosophy, distinct from science. Bergson called that method "intuition."

Core Theories

1. Duration (durée) — The Rediscovery of Lived Time

The foundational concept of Bergson's philosophy is "duration" (durée). In a word, "duration" is the time we experience from the inside — the time that no clock can measure. To see what this means, let us proceed step by step.

Start with clock time. One second, two seconds, three seconds — homogeneous units lined up along a straight line. The first second ends before the second begins; the second ends before the third begins. In this conception of time, each moment is external to every other, interchangeable, juxtaposed like points in space.

But, Bergson asks, is that really how we experience time? An hour spent in a tedious meeting and an hour spent in conversation with a close friend register as the same sixty minutes on the clock, yet as lived experiences they are utterly different. The meeting hour seems never to end, while the hour of happy conversation is over in a flash. This difference is not an illusion; the very quality of the time differs — so Bergson argued.

Bergson's favorite analogy was melody. When we listen to a melody, we do not perceive each note in isolation. The preceding note melts into the next, and the whole is experienced as a single flow. You can stop the notes and arrange them on a page — that gives you a musical score, but it is not the melody itself. A score is a spatial layout of symbols; the living experience of a melody flowing through time is something fundamentally different. Duration is time understood in the manner of this melody: the past lives on within the present, each moment interpenetrates the others, forming a qualitatively heterogeneous continuity.

Furthermore, in Creative Evolution, he introduces the famous analogy of the "sugar cube." When I drop a lump of sugar into a glass of water and wait for it to dissolve, "I must wait." This impatience or psychological weight of "waiting" is the very substance of duration. Physics can calculate the process of the sugar dissolving using equations, but that absolute fact—"that I wait"—is not included. Science measures time as a "length," but lived time is always experienced as a "quality."

The time that science deals with is, in fact, merely "spatialized time." The instant you lay time along a number line, time is transformed into space. Only spatialized time can be measured; duration itself slips through the mesh of measurement.

The implications of this distinction are momentous. If the essence of consciousness is duration, then a science that spatializes consciousness in order to analyze it will, in principle, miss the heart of consciousness. This is not a rejection of science. It is the task of determining where science is effective and where it can no longer reach.

The concept of duration also overturns the problem of freedom at its root. Determinism claims that conscious state A necessarily gives rise to conscious state B. But within duration, "state A" and "state B" are not separate, fixed units. As A unfolds, A itself changes, so that by the time B emerges, the starting A is no longer what it was. The causal chain that determinism presupposes is a fiction that holds only once time has been spatialized — Bergson argued this in Chapter 3 of the Essay.

What, then, is freedom for Bergson? It is not a choice between options A and B. The enduring self continuously brings forth a new self — and that unceasing self-creation is the very essence of freedom. Today's self takes on yesterday's experience and steps forward into something new. That step was not predetermined; it emerges from the accumulated depth of the enduring self. This is what the experience of freedom truly is.

2. Intuition — The Proper Method of Philosophy

The method for grasping duration is "intuition." This is not, however, a mystical flash or an irrational gut feeling. Consider a simple example: when a close friend is grieving, we do not analyze their facial expressions and tone of voice before concluding "they are sad." We understand their sadness by directly touching it, as it were. What Bergson means by intuition is something close to this — a mode of cognition in which one places oneself inside the object and empathetically enters its flow.

In "Introduction to Metaphysics," Bergson likens this to the difference between "looking at many photographs of a town" and "actually walking through that town." Analysis by the intellect is like taking photographs of the town from various angles and piecing them together. No matter how many photographs you add, you can never reach the absolute experience of "walking through the town" itself. Intuition is precisely this absolute cognition—entering into the interior of the town and becoming one with the object.

The intellect views its object from the outside. It analyzes, divides, and organizes by means of concepts. This operation is indispensable for practical action. But it comes at a cost: each act of division destroys the continuity of its object. Scoop water from a flowing stream — you have water in your hands, but the flow is gone. Likewise, summarize a person's life in a curriculum vitae and you obtain a list of facts, but the flow of time as actually lived — the succession of doubts, joys, and hesitations — is nowhere to be found. The intellect fixes reality in order to grasp it, but reality itself is flux.

Intuition seeks direct contact with this flux. In Bergson's own words, it is "an entering into the object by a kind of sympathy with what is unique and therefore inexpressible in it" ("Introduction to Metaphysics," 1903).

An important caveat is in order. Bergson was not dismissing the intellect. The intellect is an excellent instrument for science and technology, and intuition itself is reached only after passing through the intellect. The problem lies in assuming that intellectual cognition is the whole of cognition. Philosophy should possess its own method, distinct from that of science — this was Bergson's central claim.

3. Memory — The Past Never Disappears

Matter and Memory (1896) extended the concept of duration into the mind-body problem. Bergson began by distinguishing two kinds of memory.

The first is "habit memory" — the kind of memory inscribed in the body through repetition, such as how to ride a bicycle or how to use a language. This depends on the mechanisms of the brain and body.

The second is "pure memory." When we recall a specific scene from yesterday, we "leap" into a particular moment of the past. Bergson's bold claim was this: every past experience is preserved — not inside the brain, but within duration itself. This may sound strange at first, but Bergson's real point is as follows. Memories are not like files stored on shelves inside the brain. Rather, within duration — the flow of time in which the past dissolves into the present and keeps flowing onward — the past lives on. The brain does not "store" memories; it acts as a filter, "selecting" only those memories relevant to present action and allowing them to surface in consciousness.

There is another noteworthy argument in Matter and Memory — this one about perception. It is commonly assumed that perception consists in the brain "receiving" information from the external world. Bergson reversed this. Perception is not "addition" but "subtraction." The world already contains the totality of images. The brain subtracts what is irrelevant to action, allowing only the remainder to surface in consciousness. Perception is not passive reception but an active filtering of reality, guided by practical interest in action. An everyday example makes this clearer: when walking down the street, we are not conscious of every piece of information around us. Only what is relevant to action — the color of a traffic light, an approaching car — rises to awareness, while the rest recedes into the background. For Bergson, perception works in just this way.

He illustrated this with the image of an "inverted cone." The apex of the cone is present perception — the point of contact with the material world — while the base expands infinitely into the past of memory. When we dream, the brain's filtering function weakens, and memories that normally remain below consciousness flood in — that is how Bergson explained the phenomenon.

This position is neither materialism nor idealism. If the brain is damaged, the ability to recall memories is lost, but the memories themselves do not vanish — so Bergson argued. Late-twentieth-century neuroscience, particularly research on aphasia and memory disorders, has suggested that Bergson's intuition was partially correct. The view that the brain is not the "place" of memory but a "process" remains a leading hypothesis in contemporary neuroscience.

4. Élan Vital — The Creative Leap of Life

In Creative Evolution (1907), Bergson extended the concept of duration to life as a whole. The driving force of evolution he called the "élan vital" — variously translated as "vital impetus" or "creative impulse."

Bergson rejected two existing accounts of evolution. The first was mechanism — the position that evolution can be explained by random variation and natural selection alone. The second was finalism — the position that evolution follows a predetermined purpose.

The problem with mechanism is whether complex organs — the eye, for instance — can really be accounted for by the accumulation of tiny random mutations alone. Moreover, entirely different evolutionary lineages, such as vertebrates and mollusks, have independently developed similar organs (convergent evolution). Pure chance has difficulty explaining this correspondence. Finalism can explain it, but cannot account for the unpredictability of evolution — the appearance of genuinely novel forms that were never planned in advance.

The élan vital offers a third path beyond these two inadequate explanations. Life possesses a fundamental creative impulse from within and branches off in unpredictable directions, pushing against the resistance of matter. Evolution resembles not the execution of a blueprint but an act of improvisation. Just as a musician performing without a score cannot predict what note will come next, life creates its own path as it advances.

Bergson organized the branching of the élan vital into three broad directions. The first is the vegetative direction — life that sinks into matter, absorbing sunlight and accumulating energy in a state of insensibility. A tree does not move, yet vast stores of energy lie within it. The second is the direction of instinct — typified by insects, an ability to grasp objects from the inside. A bee builds geometrically precise hexagonal cells not by calculation or learning but by a direct bond with its object; yet this bond carries no self-awareness. The third is the direction of intelligence — typified by humans, the capacity to fabricate tools and manipulate space. From stone tools to computers, human beings have reshaped their environment through tools.

Intelligence enjoys an overwhelming practical advantage, but it cannot apprehend duration. What, then, is intuition? Bergson defined it as the attempt to go beyond intelligence and consciously recapture the "inner grasp" that instinct once possessed (Creative Evolution, Chapters 2–3).

Serious criticisms have been leveled at this concept. What does "élan vital" concretely refer to? Is it a verifiable scientific hypothesis, or merely a metaphor? This criticism will be discussed in detail later, but Bergson's aim was less to supply an alternative scientific explanation than to expose the limits of the mechanistic worldview.

5. The Two Sources of Morality and Religion — Closed Society and Open Society

In 1932, the seventy-three-year-old Bergson published his final major work, The Two Sources of Morality and Religion, extending the philosophy of duration into the domains of society and ethics.

Bergson traces morality and religion each to two distinct sources. The first is the "closed morality" and "static religion" that maintain the "closed society." Because human beings possess intellect, we are prone to question social rules, act selfishly, and risk falling into nihilism when faced with the terror of death. To counter this, nature endowed humanity with a defensive instinct called the "myth-making function" (fabulation). By generating fictions such as myths, superstitions, and the afterlife, it prevents the intellect from dissolving society, binding the group tightly together. Yet this cohesion is inherently exclusionary; it separates "us" from "them," making internal peace and external war two sides of the same coin.

The second source, which breaks through these boundaries, is "open morality" and "dynamic religion." This is the unconditional love for all humanity embodied by great mystics (les mystiques) and saints. Christ, the Buddha, Francis of Assisi—such figures act not out of social pressure, but by making direct contact with the élan vital itself and being driven by it. Their call transcends the walls of race and nation, elevating us toward a fundamental love that is open to the entirety of humankind.

The implication is crucial. Expanding closed morality quantitatively will never yield open morality. Loving one's family, then one's community, then one's nation — however large this circle grows, it remains love for "those inside a boundary," qualitatively different from a love that dismantles the boundary itself. The two moralities differ not in degree but in kind. This discontinuity is the core of Bergson's insight, and it structurally explains why internationalism repeatedly loses to nationalism.

6. Laughter — A Social Application of the Philosophy of Life

The short work Laughter (1900) represents a surprising application of Bergson's philosophy. Why do people laugh? Bergson's answer: "du mécanique plaqué sur du vivant" — the mechanical encrusted upon the living — is what produces the comic.

When a person slips on a banana peel, a body that should respond flexibly has gone rigid, like a machine. When a bureaucrat blindly follows rules and produces an absurd outcome, the capacity for flexible engagement with a living situation has been lost. Laughter is society's corrective response to this rigidity — mechanical repetition running counter to the flow of life.

This theory cannot explain every instance of laughter as a theory of comedy. But in locating the opposition between duration and intellect — between the fluidity of life and the fixity of understanding — within everyday experience, it is a fine example of how concretely Bergson's philosophy can illuminate real phenomena.

Guide to Major Works

• Time and Free Will (original: Essai sur les données immédiates de la conscience, 1889) — His doctoral thesis and starting point. The concept of "duration" is introduced for the first time. Reframes the problem of determinism and free will through the lens of time. Start here when reading Bergson.
• Matter and Memory (Matière et mémoire, 1896) — Distinguishes two kinds of memory and offers an original answer to the mind-body problem. Standing at the intersection of philosophy and neuroscience, it is challenging but deeply rewarding.
• Laughter (Le Rire, 1900) — A short work analyzing the essence of laughter. Also readable as an introduction to Bergson's thought. Brief and lucid.
• Creative Evolution (L'Évolution créatrice, 1907) — An ambitious work integrating the theory of evolution with epistemology, centered on the concept of élan vital. The masterpiece that made Bergson a worldwide name.
• The Two Sources of Morality and Religion (Les Deux Sources de la morale et de la religion, 1932) — His last major work, on the distinction between closed and open morality. An extension into political and religious philosophy.
• The Creative Mind (La Pensée et le mouvant, 1934) — A collection of essays. In the introduction, Bergson reflects on his own philosophy and gives his clearest formulation of the method of "intuition." Includes "Introduction to Metaphysics" (1903).

Major Criticisms and Controversies

1. Bertrand Russell — The Charge of Anti-Intellectualism: The most famous criticism of Bergson came from the analytic philosopher Bertrand Russell. Russell charged that Bergson fell into the contradiction of "using the intellect to prove the inadequacy of the intellect" (A History of Western Philosophy, 1945). If "intuition" is the method of philosophy, why does Bergson write books? Writing books is itself an intellectual activity.

This criticism carries a certain force, but Bergson never rejected the intellect. Intuition, he repeatedly stated, is reached by passing through the intellect; it is not its "replacement" but its "complement." Yet his failure to define the substance of intuition with full clarity did invite this misunderstanding.

2. The Einstein Controversy — Does the Philosopher's Time Exist?: The 1922 debate dealt a serious blow to Bergson's intellectual reputation. In Duration and Simultaneity (1922), Bergson elaborated his position, but he was criticized for misunderstanding the theory of relativity; in his later years he withdrew the book from reprinting.

Recent scholarship, however — above all Jimena Canales's The Physicist and the Philosopher (2015) — has shown that this debate was far less one-sided than previously thought. Bergson's point — that physics's measurement of time presupposes the lived experience of the measuring observer — raised a genuinely philosophical problem that physics alone cannot resolve.

3. The Charge of "Vitalism": The "élan vital" was dismissed by scientists as "an explanation that explains nothing." The molecular biologist Jacques Monod, in Chance and Necessity (1970), criticized Bergson as a representative of "vitalism." Invoking a "special force of life," Monod argued, amounts to the abandonment of scientific explanation.

Bergson himself, however, had presented the élan vital not as a biological entity but as a philosophical concept for understanding life as a whole. The problem of emergence — properties of a whole irreducible to the sum of its parts — remains a central concern in complexity science and philosophy of biology today.

4. Heidegger — Merely an Extension of Aristotelian Time?: In Being and Time (1927), Heidegger acknowledged Bergson's engagement with the problem of time but argued that his "duration" ultimately remained within the Aristotelian framework of "time as a succession of nows." Bergson's duration, Heidegger contended, stays at the level of psychological experience and fails to reach the more fundamental "temporality of Being." The validity of this critique is still debated today.

Influence and Legacy

Intellectual predecessors: Plotinus's doctrine of emanation (continuous generation from the One). Kant's theory of time (Bergson critically inherited the Kantian distinction between phenomena and things-in-themselves). Spencer's evolutionary philosophy — both a starting point and a target of critique. Maine de Biran and the French spiritualist tradition.

Influence on contemporaries: William James called Bergson "the greatest genius since the beginning of the world" and the two enjoyed a deep intellectual exchange. Pragmatism and Bergson's philosophy share a common tendency to value fluid experience over fixed concepts. In literature, Marcel Proust (Bergson's wife was a cousin of Proust's mother) produced In Search of Lost Time, which can be read as a literary exploration of duration and memory — though Proust himself denied any direct influence.

Relation to phenomenology: Merleau-Ponty held Bergson's theories of the body and perception in high regard and incorporated them into his own phenomenology. The concept of the "lived body" in Phenomenology of Perception (1945) is difficult to imagine without Bergson's Matter and Memory.

Revival by Deleuze: The greatest reviver of Bergson's philosophy was Gilles Deleuze. In Bergsonism (1966), Deleuze brought Bergson back to the forefront of philosophy. In Cinema 1 and Cinema 2 (1983/1985), he applied Bergson's theories of movement and memory to film theory, offering a groundbreaking analysis of the relationship between image and time. That Bergson is read again today is in large part thanks to Deleuze.

Whitehead and process philosophy: Alfred North Whitehead's "process philosophy" was deeply stimulated by Bergson's concept of duration. The perspective that views reality not as fixed "things" but as fluid "processes" has also influenced environmental philosophy and ecological thought.

Connections to the Present

Why is Bergson, nearly forgotten by the mid-twentieth century, attracting renewed attention today? Because contemporary challenges are reviving his questions in new contexts.

First, the science of consciousness and time perception. Neuroscience is revealing that the brain "constructs" time. Even within the same five minutes, subjective length varies enormously depending on the degree of attention, the intensity of emotion, and the density of memory. The problem of "lived time" that Bergson grasped intuitively is now being investigated empirically in the emerging field of chronoception.

Second, emergence and complexity. Properties of a whole that cannot be reduced to the sum of its parts — this is the contemporary version of the problem Bergson addressed with the élan vital. In complexity science, theories of self-organization, and research on the origin of life, the limits of mechanistic reduction keep resurfacing.

Third, accelerating society and the philosophy of "slowness." In a world where digital technology accelerates the flow of time and fragments attention, Bergson's proposal to "immerse oneself in duration" is not unrelated to the vogue for slow living and mindfulness. But for Bergson, this is not merely a form of therapy — it is a questioning of the very mode of cognition itself.

Questions for the Reader

• When was the last time you "lost track of time"? How did the time you were experiencing then differ from clock time — and can Bergson's "duration" help you put that experience into words?
• Will science ever fully explain consciousness? If not, is that a limitation of technology, or — as Bergson argued — a principled limitation of the scientific method itself?
• Bergson argued that expanding "closed morality" quantitatively will never produce "open morality." Does this insight explain why international cooperation repeatedly falters in today's world? Or is it too pessimistic?

References

• (Primary): Bergson, Henri. Essai sur les données immédiates de la conscience. Paris: Félix Alcan, 1889. / Eng. trans.: Time and Free Will, tr. F.L. Pogson. London: Allen & Unwin, 1910.
• (Primary): Bergson, Henri. Matière et mémoire. Paris: Félix Alcan, 1896. / Eng. trans.: Matter and Memory, tr. N.M. Paul & W.S. Palmer. London: Allen & Unwin, 1911.
• (Primary): Bergson, Henri. Le Rire: Essai sur la signification du comique. Paris: Félix Alcan, 1900. / Eng. trans.: Laughter, tr. C. Brereton & F. Rothwell. London: Macmillan, 1911.
• (Primary): Bergson, Henri. L'Évolution créatrice. Paris: Félix Alcan, 1907. / Eng. trans.: Creative Evolution, tr. A. Mitchell. New York: Henry Holt, 1911.
• (Primary): Bergson, Henri. Les Deux Sources de la morale et de la religion. Paris: Félix Alcan, 1932. / Eng. trans.: The Two Sources of Morality and Religion, tr. R.A. Audra & C. Brereton. London: Macmillan, 1935.
• (Primary): Bergson, Henri. La Pensée et le mouvant. Paris: Félix Alcan, 1934. (Includes "Introduction à la métaphysique")
• (Revival): Deleuze, Gilles. Le bergsonisme. Paris: PUF, 1966. / Eng. trans.: Bergsonism, tr. H. Tomlinson & B. Habberjam. New York: Zone Books, 1991.
• (Einstein debate): Canales, Jimena. The Physicist and the Philosopher: Einstein, Bergson, and the Debate That Changed Our Understanding of Time. Princeton: Princeton University Press, 2015.
• (Critical context): Russell, Bertrand. A History of Western Philosophy. London: George Allen & Unwin, 1945.
• (Critical context): Monod, Jacques. Le Hasard et la Nécessité. Paris: Éditions du Seuil, 1970. / Eng. trans.: Chance and Necessity, tr. A. Wainhouse. New York: Knopf, 1971.
• (Web): Stanford Encyclopedia of Philosophy, "Henri Bergson" (Leonard Lawlor & Valentine Moulard-Leonard, substantive revision 2025). https://plato.stanford.edu/entries/bergson/