All sciences use models of some variety to understand complex phenomena. In developmental sci- ence, however, modeling is mostly limited to linear, alge- braic descriptions of behavioral data. Some researchers have suggested that complex mathematical models of developmental phenomena are a viable (even necessary) tool that provide fertile ground for developing and testing theory as well as for generating new hypotheses and pre- dictions. This article explores the concerns, attitudes, and historical trends that underlie the tension between two cul- tures: one in which computational simulations of behavior are an important complement to observation and experi- mentation and another that emphasizes evidence from behavioral experiments and linear models enhanced by verbal descriptions. This tension is explored as a dialogue among three characters: Ed (Experimental Developmen- talist), Mira (Modeling Inclusive Research Advocate), and Phil (Philosopher of Science).