Optimisation and “Thoughtful Conjecturing” as Principles of Analytical Guidance in Social Decision Making

The XXth can be considered the Century of the culture of optimisation, that has been outstandingly improved and applied. There is a difference, however, between applying it to complicate technical problems, such as the war logistics, or to complex social choices, where the identification of measurable objectives and their relative weights cannot be objective and stable through time. Ex ante evaluation of actions cannot be considered as a task having an objective or scientific nature, since a part of it depends on forecasting future events, the effectiveness of which depends only on elements of systemic inertia. Despite its non-scientific basis, the use of evaluation criteria may improve, in a probabilistic sense, the quality of decisions, since, as a procedure, it contributes to confer order to the imagination of the decision makers, to reflect in qualitative terms about possible futures, to communicate, to reach consensus. Its wide use tends to produce routines, that on the one side contribute to stabilise the environment and to make it forecastable but, on the other side, tend to hinder innovative projects. Still it remains basically an art, while often it disguises itself as being objective. The associated risks are analysed in detail.