Position of Prof. Liebermann is distorted by Prager. Truth is: 1) evolution is not matter of belief, adaptation through several generations to a slowly changing environment, through selective reproduction with mutation as an unguided process is scientific fact as sure as gravity. 2) all changes from neolithic on have been too fast for evolution 3) in our natural environment food was scarce and calories diffuse so our desires are adjusted to this, so when we come across high calorie processed food our evolved response is "OMG!!! EAT!! NOW!!! you wont get another chance!!". If we evolved on planet where big macs grew on trees it would be different. So public health increased by pushing against the natural programming - coercion.