Introduction

Now that we have developed a short account of Deleuze's theory of immanent ideas, we can elaborate the rest of the problem. So far, we have only looked at the structural or ideal character of atomic and Deleuzean ideas. This part of the theory is conceptually relevant, however, only if ideas account for the emergence of actual individuals. This chapter will articulate the ways in which ideas are actualised, that is, the ways in which the atomic and differential elements, relations and singularities that compose ideas generate the determinate qualities and forms of individual things.

The next part of the theory will thus detail the distinct processes through which concretely existing individuals emerge as actualisations of atomic or differential ideas. This is different from other accounts of the generation of the world in that, for Lucretius and Deleuze, the forms or functions that actual individuals assume are not presupposed or preconstituted. Instead, forms or functions are products of, not conditions for, various genetic processes of individuation. Individuation, according to Deleuze, is truly genetic in that the form, function, goal and so on of the individual is not set beforehand. We cannot say what shape something will take before it is produced. Instead, we can only describe the ways in which something can vary as genetic material develops. What something is, or the classification under which something falls, is the result of the genetic processes emerging from the idea.

To understand what this all means, let us turn to Deleuze's second example of an idea from chapter 4 of Difference and Repetition. In that chapter, right after the mention of the atomic idea, Deleuze gives the example of the ‘organism as biological idea’ (DR 184–5). This is one of many times in which Deleuze turns to a classic debate between the eighteenth-century French naturalists, George Cuvier and Étienne Geoffroy Saint-Hilaire.

For Cuvier and other comparative anatomists, organisms are teleologically defined according to their empirical form and function. The parts of an animal, he argues, should be classified in so far as they resemble parts of other animals, with ‘man’ being the standard model.