Using the application of the Fuzzy Logic Approach to the analysis of the repertoire of personal constructs of a subject, the Implication Grid is a key starting point for the analysis of the attribution of causality and the dynamics of system of meanings. Using this approach, the subject’s system of meanings can be projected in 3D and simulated the interrelation and evolution of the individual’s system of meanings over time. This allows exploring the structure of the individual’s personal meaning system, determining its inconsistencies and projecting its evolutionary dynamics. Through this workshop we propose an innovative methodology for the study of subjectivity and the construction of the identity of the subject, the representation and mathematization of the structure and dynamics of the construction system of individuals, as well as for the study of change or the understanding of the coherence of non-change. As an application of the use of fuzzy cognitive maps, we are going to use the evaluation of subjects who want to acquire healthy habits in their lives within a health promotion program. We consider that a very promising line of research is presented, from which studies are necessary to confirm the usefulness of these tools and the fit between simulations and real changes.