Intensity

From Capitalism and Schizophrenia

To Deleuze, intensity is difference in its purest form, as a noumenon (as it is in itself) and not as a phenomenon (as it appears). (DRC 281) Intensity is to be understood in contrast of extensity, the favoured concept in state philosophy.

For example, science has traditionally been more interested in describing, even defining phenomena in terms of their extensities (e.g. surface area, distance, pressure, temperature) during a state of (imagined) equilibrium, rather than in terms of levels of intensity (states far-from-equilibrium) which is fundamental to morphogenesis, creation, productivity. In the deleuzian universe there would not even be extensities without a prior intensity. Manuel DeLanda provides the following example in his essay Deleuze and the genesis of form:

If one creates a container separated into two compartments, and one fills one compartment
with cold air and the other with hot air, one thereby creates a system embodying a difference
in intensity, the intensity in this case being temperature. If one then opens a small hole in
the wall dividing the compartments, the intensity difference causes the onset of a spontaneous
flow of air from one side to the other. It is in this sense that intensity differences are
morphogenetic, even if in this case the form that emerges is too simple.