Henri Bergson's books, and each of his classic themes, such as the primacy of time over space, the contemporaneity of the past and the present, or life as differentiation and creation, are an effort to always jump behind the dichotomies that they separate psychology and ontology, consciousness and matter, freedom and biological evolution. Gilles Deleuze proposes to go through them all from three recognized Bergsonian concepts: Duration, Memory, and Life Impulse. But these concepts are not treated as static pillars of a system that would be given from the beginning, but as stages of progress, as torsions, responses to dilemmas that force new leaps. In the progression, other concepts are becoming clearer, less recognized, but for Deleuze the motors of the movement: that of multiplicity, as opposed to the One, and that of the virtual, as opposed to the possible. Understand the problems that move thought in each moment and each level, elucidate the reason for movement, and invent the conditions of a reading. Bergsonism is a pure example of what it means for Deleuze to read a great philosopher.