What happened in the beating heart of the megalopolis of Wuhan, in China and in the crowded New York. in USA? The truth is that we don't know yet but, at dawn of 2020, we suddenly realize we are at the mercy of a virtually unknown virus. Moreover we have created the perfect environment to sustain pandemic pathogens in certain host populations. And more importantly, we have proven to be very efficient at spreading these pathogens through the extraordinary variety of transport we use today. Sars-2-CoV, the causative agent of COVID-19 has proven to be tremendously powerful in disrupting the global socio-economic system as we know it. The challenge today is how to identify obsolete pathways to abandon and find new, unexplored, alternatives. One way to do this is to be permeable to ideas from other disciplines and to fully embrace an out-of-the-box thinking approach. But before reinventing the wheel we need to look at the wheels that were built before time to understand how concepts and knowledge have evolved. For this reason the book analyses the concept of health as it began, developed and changed over the centuries. The author affirms, today more than ever, that we are responsible actors in the circle of life, and above all, guardians of the planet and defenders of its health.