The concept of elan vital seems dependent upon the importance of the key concept of virtuality. It may be too strong to suggest that the fundamental difference between life (desiring machines) and non-life boils down to the existence of virtuality, especially as virtual particles play an important role in the understanding of physical systems. Is life a composite of the real and the virtual while non life is only merely real? Again, this seems reductive but nevertheless the way in which virtuality plays an unmistakable part of conscious experience needs further exploration.

Berkeley, according to Bergson, deserves credit for the insight. “Matter has no interior, no underneath, hides nothing, contains nothing possesses neither power no virtuality of any kind is spread out as a mirror surface and is no more than what it presents to us at any given moment.”

Virtuality is the mechanism by which an object divides into differences of kind. Objective = differences in degree; subjective = differences in kind. Synthesizing any complexity necessarily transforms the operation and its objective reality. The process of dividing up leads to a change in kind. “ There is other without there being several. To be more precise, it is the virtual insofar as it is actualized, and the course of being actualized, it is inseparable from the movement of its actualization. For actualization comes about through differentiation, through divergent lines, and creates so many differences in kind by virtue of its own movement.”

The observation that things endure (a multiplicity of durations or is there only one duration?) forces us to reformulate the physical nature of space as mere exteriority. We posit a pre-geometry from which space emerges as a relationship between things or durations.

The elan vital is virtuality in the process of being actualized. Life merges into the moment of differentiation, proceeding by dissociation and division. Movement is explained by the insertion of duration into matter. The branching effect is basic to this. Movement can only happen by way of a branching effect which allows virtuality to exist across its actual divergent lines.

The virtual is not the same as the possible. The possible has no reality but may have an actuality. The virtual is not actual, but nevertheless possesses a reality. As Proust says “real without being actual, ideal without being abstract.” Deleuze continues. “The characteristic of virtuality is to exist in such a way that it is actualized by being differentiated and is forced to differentiate itself, to create its lines of differentiation in order to be actualized.”

This process can be described as creative evolution, that is, evolution is actualization of the virtual, the creation of differences.