Abstract
I defend the claim that emergence is always a kind of interaction dominance. I utilize Francescotti’s definition of emergence, which captures five features typically thought crucial for emergence: downward causal influence, novelty, relationality, supervenience, and unpredictability. I then explicate interaction dominance, a concept from complexity science. In short, a system is interaction dominant when the interactions of the parts give rise to features that override the features of the parts in isolation or linked via additive and linear dynamics. Locust swarms are presented as an illustrative case of a natural phenomenon that meets the definition for emergent properties. Moreover, locust swarms provide a case of an emergent property arising via interaction-dominant dynamics. I conclude by discussing the relationship of emergence and interaction dominance, with emphasis on the claim that all emergent properties occur due to interaction dominance, but not all systems that exhibit interaction-dominant dynamics have emergent properties.