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“We can now apply our lessons from our discussion of multilevel selection: if there are two levels of selection operating on a moral rule, then the strength of the different selective pressures will be critical in determining which of the two is more influential. If cultural competition decreases or moderates, then we can expect INDIVIDUAL-level selection to be a much stronger determinant. An interesting hypothesis thus emerges: if cultural evolution is genuinely multilevel in this way, then in eras of decreased GROUP competition, public justification of a rule should be a much stronger force in a rule's selection as it is competing for individual agents' endorsement against alternative rules. On the other hand, in eras of intense inter-group competition, we should expect that rules are not well-aligned with the moral commitment of individuals, but which are selected at the group level, may predominate.
This in turn, leads to another important point. In multilevel analysis, effective high-level GROUP selection inherently restraints lower-level INDIVIDUAL selection. There really is no point to invoking higher-level selection if it does not. In the evolution of cooperation literature, the point of invoking a GROUP-level selection is to restrain the success of INDIVIDUAL (selfish) agents so that within-group less adaptive, cooperative agents can thrive. A mammal can be seen as a case of GROUP-level selection, insofar as the possible strategies of individual cells are constrained by the adaptive needs of the GROUP (individual mammal). A cancer cell is precisely a part that has broken free of these restraints, and because of this threatens ultimately system collapse. We might say, in a rough and ready way, that restricting the social influence of INDIVIDUAL-level preferences (in which a rule's within group fitness is determined by its attractiveness to individuals) in order to secure system-wide functionality is precisely what GROUP selection accomplishes. If GROUP-level pressures are great, the rules will be less responsive to the aims of the INDIVIDUAL agents, and indeed significantly restricting their actions will be critical to the culture's success. When GROUP-level selection is strong, it is entirely appropriate to call a culture a 'superorganism.' In such a culture, rules will tend to be more restrictive, and public justification may be less important”
― Gerald F. Gaus, The Open Society and Its Complexities