6. Conclusion

The whole of this article has been devoted to the situation of a single decision-maker. Although paragraph 1.4 deals with the situation of a multiplicity of decision-makers, this was in fact no more than a metaphor to represent the temporal incoherence a decision-maker may face, with today's choices not being compatible with those of yesterday or tomorrow.

The concept of Nash equilibrium is at the heart of game theory, and enables us to analyze collective decision-making situations in which the very characteristics of the alternatives faced by one of the decision-makers are influenced by the decisions of the other decision-makers, and in which each decision-maker (referred to as a player) takes this dimension into consideration. Each player must therefore take into account the decisions of the other players, but also the weight of his own decisions on the other...