GENERALIZING EKPHRASTIC EXPRESSION A Foundation for a Computational Method to Aid Creative Design JOHN S GERO 1 University of North Carolina at Charlotte and George Mason University, United States of America 1 john@johngero.com Abstract. This paper presents the results from exploring the concept of ekphrastic expression as the foundation for a computation method to aid creative design. Ekphrasis or ekphrastic expression is the expres- sion of a concept that is represented in one medium in another sepa- rate medium. The paper describes the concepts of ekphrastic expression and presents two implemented examples that demonstrate the method and produce new results. The first example involves the creation of new shapes through representing the shape designs in the evolutionary domain and introducing new operators within that domain beyond the standard evolutionary operators of crossover and mutation. The second example involves the creation of new genes to represent aspects of Frank Lloyd Wright’s Prairie House style. This generates a space of genomes beyond those that were there at the commencement of the process. New designs that could not be directly produced in the original domain are generated. Keywords. Creative design; ekphrastic expression; design method. 1. Introduction Ekphrasis or ekphrastic expression, originally described by Plato in the Republic -Book X , is the expression of a concept that is represented in one medium in an- other medium. He used the example of a bed, which has three expressions: the physical object, the representation of the bed as an image, and the bed represented in another art form. It has been used extensively in the arts and literature such as when a scene from a poem is the basis of a painting or when a sculpture describes a dramatic event previously described in prose. This paper takes the idea of ekphras- tic expression and applies it to design through its elaboration as a computational method to aid creative design. In the arts ekphrastic expression involves the transformation of concepts rep- resented in one domain into isomorphic concepts represented in another domain P. Janssen, P. Loh, A. Raonic, M. A. Schnabel (eds.), Protocols, Flows and Glitches, Proceedings of the 22 nd International Conference of the Association for Computer-Aided Architectural Design Research in Asia (CAADRIA) 2017, 345-355. © 2017, The Association for Computer-Aided Architectural Design Research in Asia (CAADRIA), Hong Kong.