The main focus of this work is to try to answer, or at least to get close to an answer on the question of life, mainly from the perspective of science, which includes both natural sciences and philosophy. In trying to do so we get to know Austrian biologist and philosopher Ludwig von Bertalanffy and his theoretical biology, as well as his ‘organismic biology’ and ‘organismic philosophy’, but even more so General System Theory (GST) developed from Bertalanffy’s work in aforementioned fields that draw attention of scientists from other branches of science such as Kenneth Boulding (economst), Ralph Gerard (neurophysiologist) and Anatol Rapoport (mathematical psychologist) and resulted in establishing Society for General Systems Research (SGSR). While this is the central subject of this work trying to get close to an answer on the question of life, and occupies its biggest part, in order to rightly understand both work of Ludwig von Bertalanffy and main characteristics of General System Theory and its application in a philosophical investigation of the question of life, this work has to deal with historical background of both question of science and question of life. Regarding that we firstly give a historical-theoretical overview of science together with representation of the question of life in it through its three main historical periods: Greek science, Modern science, and Contemporary science. Also, lastly we represent integrative bioethics regarding it to be a frame for General System Theory as a theory mainly in the field of science, a field that integrative bioethics overcomes with its pluriperspectivistic methodology, at the same time strongly staying on the question(s) of life. Therefore, the work is specifically structured into three parts, with addition of introduction and conclusion: 1) Science and philosophy; 2) General System Theory; 3) Bioethics. In the first part, considering the question of science and philosophy, and representation of the question of life in it through its three main historial periods: Greek science, Modern science, and Contemporary science, we start with the very beginning of the Greek philosophy. In the chapter Greek science we are dealing with Greek philosophy in two historical parts: Greek philosophy up to Aristotle, and philosophy of Aristotle. The reason for this kind of parting of Greek philosophy, in contrast to the classical parting with Socrates as a point of demarcation, is that Aristotle is the first philosopher taking the question of life seriously and making it an object of his scientific thought, of what the strongest proof we see and present in his embriology. However, in both of these historical parts the question of science or, in this period the same, question of philosophy, is analysed both in regard to the very notion of science, and the question of life in science. Further in the first part we continue with analysing the question of science and philosophy through the period of Newage, named Modern science. In this chapter we start with bridging the Greek science from the former chapter and the Modern period, explicating in short a state of science in between, showing a complete lack of presence of the question of life in it. Francis Bacon is the first station hereafter, still lacking in considering life issues in his work, but proposing an emancipation of science from philosophy (and theology!), being the first to do that and in that sense building the foundation for actual separation of science and philosophy that soon came in the course of modern science. This separation came in a shape of transition from ‘subjective’ to ‘objective’ definition of science, in which philosophy, beforehand being a synonym of science, became just one branch of (humanistic) science in a row. Before we come to crisis of science that took place through nineteenth and twentieth century, we analyse a true inseparability of science and philosophy from the perspective of Kant’s metaphysics, i.e., of his understanding of objectivity of science. Crisis of natural science, but as well, we may say, of philosophy, became more than obvious in twentieth century, right after the proclamation of nineteenth century as a century of natural science, thus being challenged to aknowledge its own deviancy and impotence. In the middle of this unenviable state of science, still there grew a seed of (at least) one scientist of natural science, a biologist Ludwig von Bertalanffy, educated also in philosophy, born in a very beginning of twentieth century, which craved for more humanistic science. That leads us to last chapter of this first part of the work. In this chapter entitled Contemporary science (through the lens of contemporary philosophy and General System Theory) our research is twofold: first we examine a presence of the questions of science in contemporary philosophy, and then also the same with the questions of philosophy in contemporary science. Previous we ascertain through Husserl’s critique of science, and a philosophy of Vienna Circle, showing impoverishment, even death, of both science and philosophy without each other. While Husserl is explicitly focused on a crisis of European science and proposes what he sees as a solution for it, coming, of course, from his philosophy, i.e., transcendental phenomenology, through discussing philosophy of Vienna Circle we want to show the dangers of one-sided, solely empirical, reductionist philosophy of science, that leads in a similar crisis of philosophy as the one that has struck natural science. The last, that is, the presence of the questions of philosophy in contemporary science, we represent through scientific work and accomplishments of two scientists: physicist Ilya Prigogine and biologist Ludwig von Bertalanffy. Through two subheadings entitled Nonequilibrium thermodynamics of Ilya Prigogine, and Life as an open system of Ludwig von Bertalanffy, we analyse how the work of Ilya Prigogine in non-equilibrium physics influenced and gave way to the work of Ludwig von Bertalanffy in organismic biology and theory of open system, and how both of them managed to introduce the subject of life into the field of natural science, with the help of theoretical establishment of their ideas. This is at the same time an introduction to the second part of the work. The second part of the work entitled General System Theory is divided into two bigger chapters: the one in which we present the person, life and work of Ludwig von Bertalanffy considering the fact that he is by some called the father of General System Theory, and the second in which we present and inquire General System Theory, from its establishment and institutionalization to its main characteristics and repercussions. Regarding the first chapter on Ludwig von Bertalanffy we lean on his biographer David Pouvreau whose biography entitled The Dialectical Tragedy of the Conept of Wholeness: Ludwig von Bertalanffy’s Biography Revisited, consists of all Bertalanffy’s materials and works after 1945 that had been lost till 2004 (while all of his work up to 1945 had been burned in a fire in Vienna in the Second World War). Pouvreau is the first to take these books, articles and other publishings of Ludwig von Bertalanffy into account and represent them in Bertalanffy’s biography. In this biography Pouvreau also brings corrections to some rather inaccurate facts on Bertalanffy made so far by other authors, mainly in a shape of doctoral dissertations. Apart from that, in this chapter we also examine and present Bertalanffy’s original books relevant for this work, with the central book being entitled Modern Theories of Development: An Introduction to Theoretical Biology, and published in 1933. All of Bertalanffy’s books are written either in German (this applies mainly on his early works, written before his emigration to United States), or in English, and as far as the author is familiar, there is only one of his original works only recently translated into Croatian – his most popular book General System Theory. Foundations, Development, Applications, with the author of this dissertation being one of the reviewers. Moreover, since there isn’t any Bertalanffy’s book or even the book on Bertalanffy, in Croatian book stores or libraries (at least not yet), all of the books, weather Bertalanffy’s original works or works on Bertalanffy and his scientific achievements, that are used in this thesis are bought in an international online book store and shipped to Croatia (i.e., to author) mainly from United States. That being said, let us acknowledge specifically also the lack of any works in Croatian humanistic science on Bertalanffy’s work, especially in the field of philosophy. Regarding the second chapter of this second part of the work, where we present and analyse General System Theory, the situation is the same with the literature used for this assignment, since majority of this works is written in honor of Bertalanffy’s achievements that prepared a ground and gave way to establishing General System Theory. As we already mentioned, this chapter consists of presenting the terms in which General System Theory had been institutionalized in 1956, as well as of main characteristics of General System Theory which are, as we define them: perspectivism, open system, hierarchical organization and primary activity. In addition to that, and with tendency to clearly state what General System Theory is and what it is not, or for what kind of scientific research it cannot be applied without being destorted in itself, we bring a demarcation with help of cybernetics, at first glance the science of the same family as General System Theory, but which is in essence actually quite opposite to it. We finish the second part with researching the state of General System Theory after the life of Ludwig von Bertalanffy, i.e., after his death in 1972. Here aforementioned demarcation is further investigated considering a whole new science of systems called ‘systems technocracy’ that started to develop while Bertalanffy was still alive, in his last years, and for which he even then expressed his concern. Also, we investigate, on the positive side, application of General System Theory in social and humanistic sciences, with the emphasis on its fruitfulness for this field of science. Finally, the third and the last part of this work is dedicated to the field of bioethics in general, and integrative bioethics in particular, under the assumption that General System Theory in general and Ludwig von Bertalanffy as a scientist in particular belong to the field of integrative bioethics, and even more, are in need of integrative bioethics for their right acknowledgment as well as further development and specially application of their ideas. Not less important is General System Theory both for philosophy in general and integrative bioethics, and the fruitfulness of this theoretical concept rooted in empirical data of biology and physics for further development of the concept and project of integrative bioethics.