 From the perspective of a purely functional project, by contrast, there is less disagreement between these two views than it may initially seem. From a functionalist perspective, defenders of a causal picture and defenders of a probabilistic account can be understood as emphasizing two different aspects that both are integral features of causal models: an initial independence assumption and directed causal relationships among variables. Thus, certain criticisms of causal accounts of the asymmetry of radiation, such as Earman (2011), are most charitably understood as attacking a metaphysical account of the role of causation in accounting for radiation phenomena. Earman’s criticism cannot undermine a functional account of causation in physics, since it invokes the very same probabilistic considerations that, on a functional account, underwrite representing radiation phenomena in terms of causal models.