However, even if the examples of “downwards” causation do undermine the thesis of the causal closure of the physical, it may still be possible to rework the original argument for physicalism in terms of closure under nomological determination, rather than causal  closure.[7]  Nothing in the idea of proportional causation threatens the idea that modern physics shows that all physical effects (or their chances) are fully nomologically determined by physical antecedents, even if they aren’t always caused by them. And this in itself argues that metaphysically independent special causes would imply an unacceptable strong overdetermination of physical events.