José Antonio Leyva Galano

Group deliberation is the central topic of this dissertation. Specifically, here we study the relevance of the order of the speakers to deliberations that happen in groups. People deliberate in groups all the time. They deliberate at home, in governmental institutions or at their working place for deciding on simple or less simple matters. Naturally, the outcome of a group deliberation might be influenced by some expected factors: the different options that will be considered, the rationality of the speakers, and the accepted ways of argumentation. However, it would be unfortunate if the outcome of a deliberation was influenced by the order in which the speakers presented their arguments. This idea motivates the leading question of this dissertation: does a deliberative situation favour the first speaker of the group? Our leading question will take slightly different forms through the dissertation, and to be able to answer them we use models as a medium of representation. That is, we take a deliberative situation, we describe it as its model structure, and we answer our original question on that structure. Likewise, in the case of a similar question, this time regarding a family of deliberative situations instead of a single one, we turn the question and the scenario into a question and a scenario about a family of models. The central result of this dissertation contrasts the opinion-strength of the first speaker with the opinion-strength of any other individual that takes part in a deliberation. Broadly said, it claims that if we consider a family of possible deliberative situations, the “region” in which the first speaker has advantage is visibly larger than the one in which this does not happen. Moreover, this effect increases with the number of acceptable opinions in a debate. The previous result should be uncomfortable to any deliberative account that intends to fulfill the next two constraints at the same time: the first constraint requires that the account follows the generic structure of deliberations that we present in this work. The second one requires that from a moral, utilitarian or epistemic perspective, deliberations take place in a fair environment. Consequently, in order to be on the safe side, deliberative accounts under this category should always provide arguments that show them to be immune to this order dependence concern.