What is systems biology?

Many defined systems biology as building mathematical, computational models based on biological data to predict and retrodict future and past data. The speakers were divided roughly into biologists (data gatherers), model builders, theory builders and tool providers. Of course, many did several of these activities simultaneously. The model builders made up the overwhelming majority of speakers and posters. In addition there appears to be a split in the approach to building models. The level of ontology and abstraction ranging from low level differential equation modeling, to automata, all the way to Boolean logic. Another dimension is what to model: chemical pathways, genomic regulatory networks, cell signaling , whole cells, cell pattern formation by way of gradients.