In “Difference and Repetition,” Gilles Deleuze takes on the complex task of redefining foundational philosophical concepts like difference and repetition, often subverting conventional understandings. Here’s an overview of how he defines each term:

Difference

Traditionally, difference is understood in relation to identity or sameness; it is what separates one identical thing from another. Deleuze challenges this view by arguing for “difference-in-itself,” a kind of difference that does not depend on any underlying identity for its validation. For Deleuze, difference is not an external relation but a fundamental aspect of reality. He wants to show how difference is not just a negative concept (i.e., A is different from B) but a positive force of differentiation that produces reality itself. This notion of difference moves beyond mere opposition or negation and gets conceptualized as a dynamic, productive force.

Repetition

In common understanding, repetition is often considered the recurrence of the same element. Deleuze disrupts this understanding by introducing the concept of “repetition-for-itself.” For Deleuze, repetition is not about the return of the same but the return of difference. In repetition, each recurrence is a unique event that changes the context and meaning of what is repeated. Repetition, then, is not a matter of reproducing an identical item but rather a process that involves variation and transformation.

In summary, both difference and repetition are seen by Deleuze as active, generative forces that contribute to the becoming of reality. They are not static or merely relational terms but dynamic processes that are integral to the constitution of the world. His complex and nuanced understandings of these terms offer a departure from their conventional meanings and have been subjects of extensive discussion and interpretation in contemporary philosophy.