 This approach addresses antireductionist arguments regarding group level properties. The claim is that this new envisioning of the PNS as a purely physical law allows us to better understand the lower level origins of apparently higher level causes, thus revealing that “the appearance of ‘downward causation’ is just that: mere appearance.” (Rosenberg 2006: 197) For example, the claim is that group level selection explanations, such as are commonly given for altruism, do not require an antireductionist stance, since physical laws, such as that second law of thermodynamics, can allow for local unfavorable changes (in this case, local decreases in entropy) as long as compensation is made elsewhere. With regard to the physical PNS, 