Conventional approaches to causation in the social sciences draw on approaches in the Philosophy of Science in which a causal force acts on cases and generates change in the form of events. This relies on just one of the Aristotelian conceptions of cause - efficient cause - what brings the effect in to being. We should also pay attention to Final Cause - purpose and Formal cause, what makes something what it is and no other. The somethings are complex far from equilbric socio-ecological systems in which human agency has causal powers. This resonates with the understanding of the nature of effect in the complexity frame of reference as the state of the system both in relation to stability and transformation of kind. Effects are systems states. The argument draws on Hegel's and Dewey's understandings of cause / effect relationships as not separable but intimately interwoven. Effects have continuing reciprocal impacts on causes themselves as in positive feedback in systems. This way of thinking about causation allows us to engage with macro social change. The argument will be illustrated by a discussion of the transformation from industrial to post-industrial character across port city regions in high income countries.