Recent claims of culture in great apes have provoked fervent argument about the 'true' definition of culture, most of which has been unhelpful. Instead, a range of definitions should be used to explore different aspects of the cognitive processes that together result in human culture, many of which can be productively studied in non-humans. A richer cognitive account of the contents of culture needs to be developed and used to compare animal and human cultures, instead of sterile searching for a cognitive Rubicon between them. Exploring six views of culture, this article highlights the fundamental contrast of whether culture evolves as a by-product of cumulative change in cognitive mechanisms, or whether it is actively selected for its advantages.