Cognition and uncertainty

In the first part, we try to give a representation of the process by which man endeavours to grasp uncertainty. We propose a backward exploration which we will modelize through an influence diagram and then we can draw a few conclusions from that representation for the axiomatics of Decision.In the second part, we deal with the processing of the information formatted in such a way, regarding both its temporal complexity and its elective complexity.The first part as the second one dealing with representation and the consequences for information processing of uncertainty cognition lead to a severe criticism of the expected utility hypothesis.To conclude, we suggest a few remarks on expert systems of decision aid under uncertainty.