The term nonlinear causality refers to causation as flowing in a bidirectional or multidirectional pattern. Nonlinear causality involves cyclical processes where one thing impacts another which in turn feeds back to affect the first. With nonlinear causality, effects can be the product of many causes. Thus to gain a full understanding of the effect one need not drill down to find a single cause but instead look at multiple different factors and how they interact to give rise to the outcome as an emergent phenomenon. Equally, nonlinear causality allows for both upward and downward causation between the different levels of a system.