In the years, from a disasters perspective, risk has been dimensioned to allow a better management. However, this conceptualization turns out to be limited or constrained by the generalized use of a fragmented risk framework, which always consider first the approach and applicability of each discipline involved. To be congruent with risk definition, it is necessary to consider an integral framework, and social factors must be included. Even those indicators that could tell something about the organizational and institutional capacity to withstand natural hazards, should be invited to the table. In this article, we analyze one of the most important elements in risk formation: the social aggravation, which can be regarded as the convolution of the resilience capacity and social fragility of an urban center. We performed a social aggravation estimation over Barcelona, Spain, and Bogota, Colombia, considering a particular hazard in the form of seismic activity. The aggravation coefficient was formulated through a Mamdami fuzzy approach, supported by well-established fuzzy theory, which is characterized by a high expressive power and an intuitive humanlike manner.