Concepts of Idea

Cesare Ripa: Iconologia, overo Descrittione dell'imagini universali cavate dall' antichita et da altri luoghi. Venice 1645, 362.

The concept of the idea undergoes a fundamental change of meaning at the end of the 18th century, which is largely due to the use of the term in Kant’s transcendental philosophy. After the idea had become a synonym for any content of consciousness (representation) in early modern period, Kant redefines its meaning following Plato. In doing so, the concept has a decisive systematic function in the Critique of Pure Reason, the Critique of Practical Reason, as well as in the Critique of Judgment.

Following Kant’s transcendental philosophy, his predecessors developed the concept of idea from four different perspectives:



In 2024, a two-volume anthology on this topic will be published (together with Gideon Stiening). Its aim is to develop the concept of ideas in the late 18th century and the first half of the 19th century, based on a historical reconstruction and systematic analysis. We compile a compendium of the relevant texts (part I), comment and reflect on them analytically (part II), and, finally, present the common horizon of this development. For a list of contributing authors see the conference program from Nov. 2022: Veranstaltungen - Zentrum für Wissenschaftsgeschichte (


Published Papers (Selection)