Real freedom for all turtles in Sugarscape? - Presses universitaires ...

178A r g u i n g a b o u t j u s t i c eTables 2 and 3 (see Appendix) correspond to the first of these situationsaccording to whether or not opportunity costs are taken into account.Learning the dominant language would have a cost of 1 for Béa, whileEsperanto represents only a cost of ½. Béa then manages to convince Al andAn to also learn Esperanto and undertakes to pay them a subsidy so that thiscooperation is equitable. If the return/yield ratio of the alternative activity ofAl and An is of 11/9 and of 2 for Béa, the amount of subsidies Al and Anshould receive will be of 1/14 for each of them, which represents for Béa atax of 1/7 on top of her cost of learning Esperanto. The output of cooperationis of 7/3 for Al and An and of 28/9 for Béa. If she thus has a higher ‘return’than Al and An, it is because the return/yield ratio of her alternative activityis higher than that of Al and An. The difference between the output ofcooperation and that of the alternative activity of each agent is, however,perfectly equal and amounts to 10/9. Our revised criterion of justice is thussatisfied. Al and An will consequently each derive from cooperation a netbenefit of 4/7, while the net benefit of Béa will be of 19/14. Finally, if wesubtract opportunity costs from the gross benefits, which amount to 11/21for both Al and An and to 9/7 for Béa, we obtain the additional benefits ofcooperation in relation to the benefits that could have been produced hadthe agents devoted their contribution to their respective alternative activity.This additional benefit is of 10/21 for Al and An and of 5/7 for Béa, which isperfectly proportionate to the level of their contributions.Table 4 (see Appendix) shows what occurs if our revised criterion ofjustice is applied to the case of three linguistic communities. I kept allparameters of the initial article (BVP: 29) while factoring-in opportunitycosts for the members of A, B and C of, respectively, 9, 8 and 3. Our revisedcriterion of justice imposes/requires that each member of A contributes tothe learning of their language by those of B by paying a subsidy of 11/15 (i.e.0.733 for 0.79 without taking opportunity costs into account). Here eachmember of B receives a subsidy of 3/2 (for 1.51 without taking opportunitycosts into account). The real change concerns the member of C who musthenceforth also contribute to financing the subsidy received by the membersof B to the amount of 1/3 (while he was initially receiving a subsidy of 0.7).Our revised criterion of justice is nevertheless respected as these amountsallow each cooperant to derive from the cooperation – after subtraction ofthe opportunity cost her/his participation in it represents – a benefitperfectly proportionate to her/his contribution.