Evolutionary change is usually incremental and continuous, but some increases in organizational complexity have been radical and divisive. Evolutionary biologists, who refer to such events as major transitions, have not always appreciated that these advances were novel forms of pairwisebrcommitment that subjugated previously independent agents. Inclusive fitness theory convincingly explains cooperation and conflict in societies of animals and free-living cells, but to deserve its eminent status it should also capture how major transitions originated from prokaryote cells tobreukaryote cells, via differentiated multicellularity, to colonies with specialized queen and worker castes. As yet, no attempt has been made to apply inclusive fitness principles to the origins of these events. pemDomains and Major Transitions of Social Evolutionem develops the idea that major evolutionary transitions involved new levels of informational closure that moved beyond looser partnerships. Early neo-Darw