Henri Bergson's 1889 doctoral thesis and the foundation of his entire philosophical project — a sustained attack on the spatialisation of time in classical psychology and physics, and a defence of duration (durée) as the irreducible mode in which consciousness actually unfolds. The book argues that quantitative measurement of mental states is a category error: when we apply mathematical concepts of space and divisibility to inner life, we distort it beyond recognition. Bergson moves through three chapters — examining the intensity of psychic states, the multiplicity of conscious states, and the organization of those states — each building toward the central claim that determinism rests on a confusion between experienced time and measurable, spatialized time.
The argument reaches its resolution in Chapter III: because our genuine inner states form a qualitative, undivided flow rather than a succession of discrete units, free will is not merely coherent but is what we directly experience whenever we act from our deepest self. The book is the starting point of Bergson's influence on Proust, William James, Alfred North Whitehead, and later Gilles Deleuze, whose Bergsonism (1966) drove the late-twentieth-century revival. For readers of James's radical empiricism or of phenomenology, Time and Free Will is the French companion text that reached many of the same conclusions from different premises.
Pure duration is the form which the succession of our conscious states assumes when our ego lets itself live, when it refrains from separating its present state from its former states.
Chapter II, "The Multiplicity of Conscious States"
First lines
The problem which I have chosen is one which is common to metaphysics and psychology, the problem of free will. What I attempt to prove is that all discussion between the determinists and their opponents implies a previous confusion of duration with extensity, of succession with simultaneity, of quality with quantity: this confusion once dispelled, we may perhaps witness the disappearance of the objections raised against free will, of the definitions given of it, and, in a certain sense, of the problem of free will itself.
Contents
Chapter I: The Intensity of Psychic States
Chapter II: The Multiplicity of Conscious States: The Idea of Duration
Chapter III: The Organization of Conscious States; Free Will
Reception
One of the foundational texts of 20th-century continental philosophy and the work that established Bergson's framework before Matter and Memory (1896) and Creative Evolution (1907) extended it. Massively influential during his lifetime — Bergson was a celebrity philosopher in pre-war Paris and a Nobel laureate in Literature (1927) — and a direct influence on Proust, William James, Whitehead, and later Deleuze, whose Bergsonism (1966) drove the late-20th-century revival. Eclipsed by phenomenology and analytic philosophy in the mid-century, Bergson's reputation has steadily recovered since the 1990s, with this work treated as the indispensable starting point. The Dover paperback translation by F. L. Pogson (originally 1910) remains the standard English edition.
Frequently asked
What is Bergson's main argument in Time and Free Will?
Bergson argues that free will is intelligible once we distinguish two kinds of time: spatialized, measurable time (the kind physics uses) and pure duration — the qualitative flow of consciousness as actually experienced. Determinists confuse the two. When we act from our deepest self, that act is free precisely because it flows from an undivided, continuously evolving inner life, not from a sequence of fixed, calculable states.
What is "duration" (durée) in Bergson's philosophy?
Duration is Bergson's term for lived, experienced time — a continuous, qualitative flow in which past and present interpenetrate rather than standing as separate, countable moments. It is opposed to the homogeneous, measurable time of clocks and physics, which Bergson argues is a spatial representation of time rather than time as directly lived.
Who was influenced by Bergson's Time and Free Will?
The book directly influenced Marcel Proust (whose exploration of involuntary memory draws on Bergson's duration), William James (who cited Bergson as a fellow radical empiricist), Alfred North Whitehead (process philosophy), and, in the late 20th century, Gilles Deleuze, whose Bergsonism (1966) revived Bergson for French philosophy and introduced him to a new international readership.