Here we discuss the application and articulation of biological principles for mathematical modeling of morphogenesis in the case of mammary ductal morphogenesis, with an emphasis on the default state.
Abstract
Unlike inert objects, organisms and their cells have the ability to initiate activity by themselves, and thus change their properties or states even in the absence of an external cause. This crucial difference led us to search for principles suitable for the study organisms. We propose that cells follow the default state of proliferation with variation and motility, a principle of biological inertia. This means that in the presence of sufficient nutrients, cells will express their default state. We also propose a principle of variation that addresses two central features of organisms, variation and historicity. To address interdependence between parts, we use a third principle, the principle of organization: more specifically, the notion of the closure of constraints. Within this theoretical framework, constraints are specific theoretical entities defined by their relative stability with respect to the processes they constrain. Constraints are mutually dependent in an organized system and act on the default state. Here we discuss the application and articulation of these principles for mathematical modeling of morphogenesis in a specific case, that of mammary ductal morphogenesis, with an emphasis on the default state. Our model has both a biological component, the cells, and a physical component, the matrix that contains collagen fibers. Cells are agents that move and proliferate unless constrained; they exert mechanical forces that i) act on collagen fibers and ii) on other cells. As fibers are organized, they constrain the cells’ ability to move and to proliferate. This model exhibits a circularity that can be interpreted in terms of the closure of constraints. Implementing our mathematical model shows that constraints to the default state are sufficient to explain the formation of mammary epithelial structures. Finally, the success of this modeling effort suggests a step-wise approach whereby additional constraints imposed by the tissue and the organism can be examined in silico and rigorously tested by in vitro and in vivo experiments, in accordance with the organicist perspective we embrace.
The contributive economy is a strategy to disrupt technological disruption by developing knowledge in all its forms. This program has led to several concrete working groups in Plaine Commune.
Abstract
The program Plaine Commune, contributive learning territory, started in late 2016. It emerged from the theoretical work of Bernard Stiegler and the Ars Industrialis group. The contributive economy is a strategy to disrupt technological disruption by developing knowledge in all its forms. This program has led to several concrete working groups in Plaine Commune, while others are still developing. Mainly, work is taking place on the economy, digital urbanism, and young children’s development in the context of the overuse of digital media. Here, we focus on the group on digital media and young children’s development and how academics and inhabitant works integrate.
Quelques remarques sur la pertinence de la philosophie de Canguilhem sur les enjeux contemporains, de la medecine par la preuve à la disruption des organisations biologiques.
In biology, randomness is a critical notion to understand variations; however this notion is typically not conceptualized precisely. Here we provide some elements in that direction.
Abstract
Physics has several concepts of randomness that build on the idea that the possibilities are pre-given. By contrast, an increasing number of theoretical biologists attempt to introduce new possibilities, that is to say, changes of possibility space – an idea already discussed by Bergson and that was not genuinely pursued scientifically until recently (except, in a sense, in systematics, i.e, the method to classify living beings). Then, randomness operates at the level of possibilities themselves and is the basis of the historicity of biological objects. We emphasize that this concept of randomness is not only relevant when aiming to predict the future. Instead, it shapes biological organizations and ecosystems. As an illustration, we argue that a critical issue of the Anthropocene is the disruption of the biological organizations that natural history has shaped, leading to a collapse of biological possibilities.
A new look at theoretical computer sciences by changing perspective with a biological approach.
Abstract
The analogy between living beings and computers was introduced with circumspection by Schrödinger and has been widely propagated since, rarely with a precise technical meaning. Critics of this perspective are numerous. We emphasize that this perspective is mobilized to justify what may be called a regressive reductionism by comparison with physics or the Cartesian method. Other views on the living are possible, and we focus on an epistemological and theoretical framework where historicity is central, and the regularities susceptible to mathematization are constraints whose existence is fundamentally precarious and historically contingent. We then propose to reinterpret the computer, no longer as a Turing machine but as constituted by constraints. This move allows us to understand that computation in the sense of Church-Turing is only a part of the theoretical determination of what actually happens in a computer when considering them in their larger theoretical context where historicity is also central.
Si la philosophie est entrée en stasis et se porte vers un nécessaire Autre Commencement de la Philosophie, alors les sciences aussi sont à un autre commencement.
Abstract
Ce texte est le séminaire public donné le 31 mai à l’École Normale Supérieure de Paris. Les sciences se sont écartées de la philosophie. Si la philosophie est entrée en stasis et se porte vers un nécessaire Autre Commencement de la Philosophie, alors les sciences aussi sont à un autre commencement. L’Anastasis des sciences exige une enquête sur la persistance des concepts théologiques en leur sein et en même temps la découverte de nouveaux principes par lesquels les sciences peuvent recommencer de telle manière qu’elles soient libérées des fardeaux métaphysiques. Les homologies d’un autre commencement des sciences sont déjà visibles dans les crises conceptuelles, y compris dans les concepts de singularité en physique et d’immunité en biologie. Pour commencer à nouveau, une épistémologie bâtarde est proposée comme nouveau rapport entre les sciences et la famille bâtarde de la déconstruction.
We question some aspects of medicine from the perspective of theoretical biology, on the one hand, and the technological and social dimension of health and disease on the other hand.
Abstract
Technological developments in genomics and other -omics originated the idea that precise measurements would lead to better therapeutic strategies. However, precision does not entail accuracy. Scientific accuracy requires a theoretical framework to understand the meaning of measurements, the nature of causal relationships, and potential intrinsic limitations of knowledge. For example, a precise measurement of initial positions in classical mechanics is useless without initial velocities; it is not an accurate measurement of the initial condition. Conceptual and theoretical accuracy is required for precision to lead to the progress of knowledge and rationality in action. In the search for accuracy in medicine, we first outline our results on a theory of organisms. Biology is distinct from physics and requires a specific epistemology. In particular, we develop the meaning of biological measurements and emphasize that variability and historicity are fundamental notions. However, medicine is not just biology; we articulate the historicity of biological norms that stems from evolution and the idea that patients and groups of patients generate new norms to overcome pathological situations. Patients then play an active role, in line with the philosophy of Georges Canguilhem. We argue that taking this dimension of medicine into account is critical for theoretical accuracy.
Postface de La révolution contributive, 2022, Pierre Giorgini, ISTE Editions
Abstract
La révolution contributive résulte du passage rapide à une conception dominante des systèmes (techniques, sociaux, organisationnels, culturels, etc.) où chacun des composants des systèmes co-élabore la performance du tout, en dehors de tout pilotage et contrôle centralisé et extérieur au système. Elle réinvente fondamentalement la relation sujetobjet.La révolution contributive en cours est globale et profonde. Elle apparaît comme une solution possible à la crise économique, écologique et politique qui frappe les sociétés contemporaines, elle concerne tout le champ épistémologique, des sciences jusqu’aux organisations sociales (épistémè).
The collective work that produced this book is based on the claim that today's destructive development model is reaching its ultimate limits, and that its toxicity is generated above all by the fact that the current industrial economy is based on an obsolete physical model.
Abstract
Bifurcating means: reconstituting a political economy that reconnects local knowledge and practices with macroeconomic circulation and rethinks territoriality at its different scales of locality; developing an economy of contribution on the basis of a contributory income no longer tied to employment and once again valuing work as a knowledge activity; overhauling law, and government and corporate accounting, via economic and social experiments, including in laboratory territories, and in relation to cooperative, local market economies formed into networks and linked to international trade; revaluing research from a long-term perspective, independent of the short-term interests of political and economic powers; reorienting digital technology in the service of territories and territorial cooperation. The collective work that produced this book is based on the claim that today’s destructive development model is reaching its ultimate limits, and that its toxicity, which is increasingly massive, manifest and multidimensional (medical, environmental, mental, epistemological, economic – accumulating pockets of insolvency, which become veritable oceans), is generated above all by the fact that the current industrial economy is based in every sector on an obsolete physical model – a mechanism that ignores the constraints of locality in biology and the entropic tendency in reticulated computational information. In these gravely perilous times, we must bifurcate: there is no alternative.
Comment concevoir et réaliser des plateformes numériques au service des relations sociales et intergénérationnelles, aujourd’hui menacées par les applications addictives et l’économie des données ?
Abstract
Lorsque les technologies numériques sont mises au service de l’économie des données, leur design et leur fonctionnement exploitent les attentions, afin d’orienter, voire de contrôler, les comportements des utilisateurs. Réduits à un ensemble de processus cognitifs et de réactions réflexes, ils se voient dépossédés de leurs savoirs, alors même que, dans nos sociétés en situation de crise sanitaire, sociale, politique et écologique, le partage et la transmission des savoir-faire, des savoir-vivre et des savoir-penser sont plus que jamais nécessaires. Comment concevoir et réaliser des plateformes numériques au service des relations sociales et intergénérationnelles, aujourd’hui menacées par les applications addictives et l’économie des données ? Comment intégrer dans les dispositifs computationnels des fonctions délibératives et interprétatives ? Comment transformer les technologies numériques en supports de mémoire et de savoirs ? Comment mettre les algorithmes au service de l’intelligence collective ? En un mot, comment prendre soin de l’informatique pour les générations actuelles et à venir ? Ce livre interroge la manière dont les supports techniques configurent nos capacités psychiques et nos relations collectives, et propose des solutions pour concevoir de nouveaux dispositifs et de nouvelles pratiques, afin de mettre les technologies numériques au service de la production et de la transmission de savoirs, ainsi que des liens entre les générations.
