In the early 1960s, Jacob and Monod suggested that genetic networks, in which a transcription factor coded by one gene acts as a regulatory input to another gene, could underlie cellular processes such as differentiation and oscillation. These notions led to early theoretical studies by Tomita, Thomas, Kauffman, Glass, and others that developed a theoretical framework for analyzing logical interactions in genetic networks. In recent years, logical circuits have reappeared in a variety of applications including the synthesis of the toggle switch and repressilator, and the analysis of differentiation in Drosophila, Arabidopsis, and sea urchin. This talk poses the
question: Are logical models sufficiently close to what really happens in biology that they provide an appropriate method to relate the logic and dynamics of biological circuits? Depending on the answer to this question it would either make sense to: (i) make the mathematical methods for analysis of these systems better known to biologists; or (ii) search for a new theoretical construct.