  The dispute between those who regard weak altruism as individually advantageous, and those like Wilson who regard it as group advantageous, stems ultimately from differing conceptions of individual and group selection. For Wilson, individual selection means within-group selection, so to determine which strategy is favoured by individual selection, one must compare the fitnesses of W and N types within a group, or pair. For other theorists, individual selection means selection based on differences in individual phenotype, rather than social context; so to determine which strategy is favoured by individual selection, one must compare the fitnesses of W and N types in the same social context, i.e., with the same partner. These two comparisons yield different answers to the question of whether weak altruism is individually advantageous. Thus the debate over how to classify weak altruism is intimately connected to the broader levels of selection question; see Nunney 1985, Okasha 2005, 2006, Fletcher and Doebeli 2006, West et al. 2007, for further discussion.