Walter Hermann Nernst (1864-1941), the great German scientist, winner of the Nobel Prize in Chemistry (1920) and father of the third principle of thermodynamics, had a Florentine pupil, Giorgio Piccardi (1895-1972), Professor of Physical Chemistry at the University of Florence. Piccardi launched the studies of oscillating phenomena, which were then undertaken by Ilya Prigogine (1917-2003), the scientist awarded the Nobel Prize in Chemistry in 1977. Piccardi’s best pupil and scientific successor was Enzo Ferroni (1921-2007), who took over his chair at the Department of Physical Chemistry at the University of Florence. Enzo Ferroni had a young, enterprising researcher from Siena as his pupil, Enzo Tiezzi, who then became Full Professor of Physical Chemistry and founder of the Sienese School of Chemistry. Mindful of this lineage and extremely respectful of the role of his teachers, Enzo Tiezzi often spoke proudly of having been a pupil of Giorgio Piccardi, Enzo Ferroni, and Ilya Prigogine.
Enzo passed away June 25th, 2010.
Enzo Tiezzi was a scientist, an internationally famous physical chemist. In order to tell about his academic career, we would have to mention hundreds of publications and university lectures. His research was a journey, a series of adventures undertaken with the spirit of a passionate pioneer. From his years studying magnetic resonance imaging to his research in the sectors of evolutionary and ecological sciences, Enzo Tiezzi was an authentic precursor of the sciences and new disciplines for the environment, up to his recent studies on the complex properties of water .
It is impossible to summarize, in just a few lines, the work of Enzo Tiezzi, and the immense, protean, colorful baggage of knowledge gained and transmitted in these years of passionate scientific research. Wishing to identify a general, preeminent aspect of his thought, we believe we must refer to his great ability to observe and explain, in theoretical terms, the behavior of complex dynamic systems. In his thought, thermodynamics is the science that predominantly allows for the explanation of the general processes that regulate the functions of living systems, and that allows us to face existential issues such as the origin and maintenance of life on planet Earth, or the complexity and emergence of novelties in nature. With this basic direction, the scientific investigations of Enzo Tiezzi have ranged from laboratory studies of a number of particular oscillating chemical reactions, to the systemic vision of networks of processes in living organisms, ecosystems, economic and social systems. An accurate and articulate scientific treatment of the recent developments of evolutionary sciences and the epistemology of science is gathered in the volume “Steps Towards an Evolutionary Physics”, which furthers the work undertaken by Prigogine.
Prigogine defined these systems as dissipative structures for their ability to organize themselves into coherent forms and to maintain them over time. These properties are due to two essential and necessary characteristics. The first is that a dissipative system is an open system, that is related to the external environment with which it activates exchanges of energy and matter. The second is that a dissipative structure is a complex system with a group configuration that is coherent and able to adapt itself to stimuli from the surrounding environment and to self-organize. Tiezzi investigated the main properties of living systems, starting with the thermodynamics of Prigogine. In recent years, in order to more simply identify and communicate the basic principles of an ecological theory of systems that is able to orientate new techniques for observing nature, Tiezzi focused attention on a concept that he synthetically expressed with the acronym COOS, with reference to the name of the Greek island that is the home of Hippocrates. COOS means “Confined Ontic Open System”, indicating that every living system or grouping of living systems – which could be a garden or a barena in the lagoon of Venice – is one of a kind, insofar as it is the result of an epigenetic evolutionary process in which different elements and systems have combined in a succession of random choices and events. The self-organization of a system is guaranteed by the presence of a border, an interface that allows for the modulation of the relations and exchanges between the system and the external environment and conditions its evolution. The idea was born in Morocco, in February 2009, when Enzo was in the house of his friend Sergio Caroli, built renewing an ex-caravanserai in the Tighmert oasis.
While speaking of Tiezzi’s work, a colleague and friend, Prof. Enrico Falqui, said, “his last years were spent in attempting to track down ‘universal values’ in the field of his complex and countless investigations into the link between Biology and Development; when Enzo did track them down, he then chose new tools and new means for ‘communicating’, to an increasingly wider audience, his ideas for the future and the ethics of responsibility, which he always knew how to convey to his pupils.” In these years, Enzo Tiezzi founded and directed the Ecodynamics Group. Today, this group has the honor of availing itself of the strong imprinting that Enzo Tiezzi entrusted to his pupils in these years of collaboration and research. Enzo Tiezzi’s perspective and inheritance, gathered in particular in his books and publications, is today the common key for interpreting all the interdisciplinary works and projects undertaken by this research group, in remembrance of his first teachings (quoting Seneca): “If one does not know to which port one is sailing, no wind is favorable.”
In these years of passionate collaboration, we have seen Enzo Tiezzi receive all kinds of awards and recognitions, each time with the pride and gratitude of one who still knows how to be amazed by the approval he has gathered. He always held this spirit, for occasions of great prestige among international scientists – such as for the Blaise Pascal Medal of the European Academy of Science, or for the Prigogine Medal of the Wessex Institute of Technology – as much as for all other cases, which were just as important in his eyes – such as for the Mantova Award for Arts and Sciences, or the ‘Mangia d’Oro’, a recognition granted by the city of Siena to its greatest representatives.
Books by Enzo Tiezzi, scientific essays written with the sensibility of a narrator enchanted by nature – such as “The End of Time” , “Beauty and Science” , “The Essence of Time” , among others [6-8] – have influenced hundreds of young researchers and have been translated and published all over the world. An interview with him was included in the International Show "Les Yeux ouverts. Stock exchange visions"  and presented at the Centre Pompidou in Paris, at the Milan Triennial, and at the Shanghai Arts Festival: this is a set of interviews of 54 personalities, including scientists and world-famous intellectuals, accredited with and chosen for giving a “vision of the future world”.
In his attempt to identify the reasons for the global environmental crisis, Enzo Tiezzi directed our gazes towards the difference between the extremely fast times of technology and the slow times of biology; here we are dealing with a formidable scientific intuition – as Enrico Falqui writes again – that underlines the reversal between the scale of Historical Times and that of Biological Times, caused by the imbalances and uncontrolled growth provoked by human activity since the 1950’s. His most celebrated book carries the “trademark” of this pioneering idea: The End of Time , on the eve of the referendum on the use of nuclear energy in Italy and the terrible incident that occurred in Russia at the Chernobyl nuclear reactor. Enzo Tiezzi taught that the problem of sustainability is therefore a problem of time, and in particular of the distance that is growing between Historical Times and Biological Times. As to this breach, he wrote in 1984 in the first edition of his book: “Entropy means waste of resource and pollution, energy crises and destruction of the environment. […]Dominant economic theory, based as it is on mechanistic principles, remains ignorant of the law of entropy and the role of the time variable. The classical dynamic concept of time and its reversibility, has nothing to do with reality and nature. Time is not without its preferred directions (it is not isotropic) as is space. Time has a direction. […] Not only is economics ignorant of these concepts, but it introduces another concept which can be summed up as «time is money». Progress is measured by speed of production. It has even been suggested that the faster we use up nature's resources, the greater the advance of progress. In other words, the faster we transform nature, the more time we save. This technological or economic concept of time is exactly the opposite to «entropic time». Nature obeys different laws to economics, it works in «entropic time»: the faster we consume natural resources and the energy available in the world, the less time is left for our survival. «Technological time» is inversely proportional to «entropic time»; «economic time» is inversely proportional to «biological time».
Our limited resources and the limited resistance of our planet and its atmosphere clearly indicate that the more we accelerate the energy and matter flow through our Earth system, the shorter is the life span of our species. An organism which consumes faster than the environment produces cannot survive, it has chosen a dead branch of the evolutionary tree; it has chosen the road taken by the dinosaurs. Money time and clock time are not the scales on which a correct relationship with nature can be established. Paradoxically the clock which is a symbol of order, strikes the hours of disorder; frenetic consumerism and growth of production advance the hour of global disorder. The natural order has other rhythms, another time scale. Man cannot stop time but he can slow down the process of entropy and evolution which will favour a transition to a state of minimum entropy production and, in the long run, favour the future of our species”.
His journeys, from India to Patagonia, from Guatemala to Cappadocia, and his observations of the infinite diversities among nature, cultures, and civilizations, always inspired his work, aimed at the constant search for beauty in this “blue orange” – as Enzo defined our magnificent planet – and at an authentic harmonious relationship with it. His wisdom was expressed in a thousand ways, with great coherence, such as in his photographs , which have often been exhibited in various cities in Italy, and in his poetry [11,12], which testifies to his being both a meticulous scientist and a passionate creative artist.
In order to give an idea of the eclectic personality of Enzo Tiezzi, we must refer to numerous meetings with him and how much was absorbed from each of them, if they were with Nobel Award-winners or world-famous intellectuals and scientists, or with his youngest pupils. Many have treasured his teachings for studies and applications in numerous sectors and disciplines, grateful for the passion for science and life that he was able to convey.
Much of his exuberant nature manifests itself between the lines of his stories. Enzo is in all and in none of the various characters, only partly real or completely imaginary, that populate the pages of his novels [13-15], each of which, in some way, represent an aspect of his multifaceted personality. In order to tell you about him, we would have to quote Rosaluna, born February 4th in a thermal tub, Altair the horse, the sketched character Indaco de Lunas, the city and the young girl Asmara, a talking pelican named Polibio, the dreamer Isidro Pavòn, the king of the gypsies and the pirate Morgan, and, finally, we would have to tell you about his casual encounter with a two-tailed mermaid.
The Pupils - Ecodynamics Group.
 Special issue of the International Journal of Ecodynamics, 5 (1), 2010.
 E. Tiezzi. Verso una fisica evolutiva. Donzelli, Roma, 2006; Steps Towards an Evolutionary Physics. WIT Press, Southampton, UK, and Boston, USA, 2006.
 E. Tiezzi. Tempi Storici, Tempi Biologici: venticinque anni dopo. Donzelli, Roma, 2005; The End of Time. WIT Press, Southampton, UK, and Boston, USA, 2003.
 E. Tiezzi. La Bellezza e la Scienza. Cortina, Milano, 1998; Beauty and Science. WIT Press, Southampton, UK, and Boston, USA, 2004.
 E. Tiezzi. Fermare il Tempo. Un’interpretazione estetico-scientifica della natura. Raffaello Cortina, Milano, 1996; The Essence of Time. WIT Press, Southampton, UK and Boston, USA, 2003.
 E. Tiezzi e N. Marchettini. Che cos’è lo sviluppo sostenibile? Donzelli, Roma, 1999.
 F. Pulselli, S. Bastianoni, N. Marchettini, E. Tiezzi. La Soglia della Sostenibilità. Ovvero quello che il Pil non dice. Donzelli, Roma, 2007; The Road to Sustainability. GDP and the Future Generations. WIT Press, Southampton, UK, and Boston, USA.
 R. M. Pulselli, E. Tiezzi. Città Fuori dal Caos. La sostenibilità dei sistemi urbani. Donzelli, Roma; City Out of Chaos: Self Organization and Sustainability. WIT Press, Southampton, UK, and Boston, USA.
 Les Yeux ouverts. Stock exchange visions. Available at: http://www.stockexchangeofvisions.org/
 E. Tiezzi. Lo sguardo sul pianeta. Immagini di biodiversità planetaria tra sostenibilità ambientale e sacralità naturale. Laris ed., Colle Val d’Elsa, Italy, 2010.
 E. Tiezzi. Di terra, di aria, di mare. Marcos y Marcos, Milano, 2006.
 G. Moro, E. Tiezzi. Canto e controcanto. Marcos y Marcos, Milano, 2009.
 E. Tiezzi. Rosaluna. Donzelli, Roma, 2006; Rosaluna. WIT Press, Southampton, UK, and Boston, USA, 2010.
 E. Tiezzi. Isidro Pavòn. Ovvero la storia del canale che mai fu. Donzelli, Roma, 2008.
 E. Tiezzi. Asmara. Donzelli, Roma, 2009.
WIT's Memories of Enzo Tiezzi
The Wessex Institute of Technology immensely regrets the death of our friend and colleague Professor Enzo Tiezzi. He was a towering personality in the ecological systems field and through his pioneering work following Prigogine’s ideas. Enzo’s official title was Professor of Chemistry at the University of Siena, but his interests were wider, ranging from poetry to chemistry. He was a true Renaissance man, bringing new ideas and deeper insight to all fields of knowledge. He was able to discover the essence of different phenomena. His contributions to evolutionary processes and ecosystems in particular have been enormous.
WIT will sorely miss him because of his involvement in many of the Institute’s activities. WIT Press is proud of having published scientific books co-authored by Enzo and his researchers as well as a novel, which gives an idea of the breadth of his interests. He was Co-Editor of many WIT Press books and a main Editor of the International Journal of Design & Nature and Ecodynamics, which has recently put together an outstanding issue on the Nature of Water, which Enzo expressed a special wish to see before his departure.
It will take too long to describe the major works of Enzo and his collaboration with WIT. It is important however to point out that he was the prime motivator behind the establishment of the Prigogine Gold Medal Award, instituted by the University of Siena and the Wessex Institute of Technology, following the death of Professor Ilya Prigogine in 2003. This important award has been given every year since 2004 to the best researcher working in the field of ecosystems modelling, particularly those following the work of Prigogine. Enzo received the award in 2005 at the Aula Magna of the University of Cadiz. He was also a Director and Fellow of the Wessex Institute, who awarded him the Eminent Scientist medal in 2003. Enzo received many other awards and recognitions during his career.
Enzo was a man of integrity and died in accordance with his principle. He had what Spanish speakers call a ‘good death’ (una Buena Muerte) which is an idea that conveys not death itself but a sense of closure. He was aware of the terminal nature of his disease but with tremendous courage, decided not to try to prolong it as usual by treatment or surgery. He waited patiently to the end surrounded by a loving family and community.
His life continues in the work of the many researchers that he has guided over his long and prolific career. It also perdures in his books, papers, poems and other works; a legacy that will live for ever after his departure. Finally, and equally important he was for all the members of our community a good friend in which you could always rely in times of need.
Professor Carlos A Brebbia
Wessex Institute of Technology