**4.2 Field data**

In natural situations, this type of characterisation applies to events which appear to be quite different from the outside but which are relatively similar as regards their underlying architecture and organisation. The media report these events regularly when they have harmful effects.

The events most frequently encountered are:


implemented in the countries of the European Community, federated around a common project, reveals, both in terms of time and structure, major differences in the way the situation is processed and the decisions made.

In all these categories (the types of situation which have just been mentioned), the decision-makers encounter major difficulties in managing the active systems not only individually but also as a committee: the collective intelligence so often proposed as the solution is temporarily inoperative. Some forest fires last for weeks, even months, damaged oil tankers continue to spill their cargoes for weeks and sometimes much longer, the issue of global warming proves difficult to manage, like the pandemic which, since the alert was raised in 2019, has not yet been controlled at the time this document was written.

In view of such obvious and recurrent difficulties, we must examine the methods and cognitive strategies involved in the decision-making process when faced with complex systems.
