 There is no doubt that it is often important to remind overly-enthusiastic orthodox Darwinians of the importance of culture. For example, it seems that the increased incidence of lactose-tolerance among human populations has arisen as a consequence of a cultural innovation—namely dairy farming. The relatively recent appearance of this genetically-controlled adaptation demonstrates that human physiological nature is something that continues to change, and it also demonstrates the causal impact of culture on genes (Richerson and Boyd 2005, 191–92). Such examples by themselves show the rashness of any view that claims either that human nature has remained fixed since the Stone Age, or that genes are somehow in the evolutionary driving seat. Yet none of this shows that we can develop a general, informative theory of cultural evolution. One might fear that in the end cultural change, and the influence of cultural change on other aspects of the human species, are best understood through a series of individual narratives. Our brief examination of memetics illustrated this concern. We gain no real explanatory insight if we are told that ideas spread through populations, some more successfully than others. We want to know what makes some ideas fitter than others. And it is not clear that there will be any general rules that can help us to answer this question. In the biological realm we need detailed accounts of local environmental circumstances, species-specific physiology and anatomy, and so forth, to tell us what makes one organic variant fitter than another. Similarly, in the cultural realm we will need to look at local psychological dispositions to explain why some ideas are more likely to spread than others. So any explanatory value to be had from memetics is parasitic on conventional work done in psychology. And if individual preferences are subject to change over time, then there may be no general and informative theory of cultural evolution to be had; rather, we will have to settle for local explanations that look to shifting preferences. Rather than provide a new scientific framework for an understanding of culture, memetics will tend to degenerate into conventional narrative cultural history.