In Chapter 6, I discuss the way knowledge and skills evolve culturally. Starting from the notion of cumulative cultural evolution, I show how the emergence of arithmetical knowledge and skills can be understood as the product of trans-generational cultural evolution. Cumulative cultural evolution, however, requires a particular type of social learning, called cultural learning in the literature. To make sense of this problematic notion, I propose the non-circular characterisation of cultural learning as learning that takes place through processes of passing information that are clearer, less ambiguous and more enduring than other forms of social learning. I also present an account of how innovation of new contents is possible in the framework of cultural learning and cumulative cultural evolution. Finally, I evaluate the five predictions made in Chapter 3 from the perspective of phylogeny and cultural history.