Prof. Francesco dell’Isola is co-author of more than 164 papers (indexed in Scopus). He was editor or co-author of 5 technical books published in Springer Nature, also. He supervised or co-supervised more than 20 Ph.D. students and 10 postdoctoral projects. He gave more than 70 invited lectures in several universities and international conferences and has been Visiting Professor in more than 7 universities (France, USA, and Russia). In 2018, he has been Russell Severance Springer Professor at the University of California, Berkeley. His research interests are in several fields of theoretical mechanics and applied mathematics: the common techniques used are variational principles, as a heuristic tool for formulating mathematical models. In particular, he has studied the possible applications of Lagrangian mechanics methods to social sciences and economy and the present book popularises some of the most important results in this field.