After the disruptions brought, also to the macroeconomic scenario, by phenomena such as the COVID-19 pandemic and the invasion of Ukraine, it is likely that the theme of secular stagnation of economic growth, taken up again in 2013 after Alvin Hansen’s original contribution, will once again occupy a central place in geo-economic research and analysis, not least because of its empirical validation. The dominant paradigm, at least since the beginning of the 20th century, not only in the so-called exact sciences, but also in other areas of the social sciences such as economics, has been characterised by determinism, almost unlimited trust in linear models, their conclusions, and their near infallibility. The lack of precision of these models has been evident, particularly in what is supposed to be their great strength, that is, their predictive capacity. Events such as the financial crisis of 2007/2008, the European sovereign debt crisis, the significant increase in the contribution of emerging markets to the global wealth, have shown how these linear models are limited and, also for this reason, are likely to be viewed with some skepticism by decision-makers. Given this conceptual framework, we intend to revisit the secular stagnation thesis, in its fundamental theoretical foundations, but also in the empirical evidence with the most recent data and, in addition, to look at an alternative vision to the mainstream. This vision is embodied by complexity theory, with its conviction that phenomena don’t necessarily behave in a linear model, so it’s difficult to identify one that covers all the characteristics under study, imbalance is the usual characteristic of systems and, finally, disorder, not order, is typically the situation in systems. Seieing these approaches as a complement to, rather than a break with, the mainstream, we ultimately tried to remain faithful to the founding principles of science, starting with openness to change, to new working methods, to new paradigms.