The laws of nature are considered to be objective, universal, and invariable descriptions. They structure our understanding of reality, they create physics, they frame cosmological models. And yet, one question remains in the background that is rarely formulated explicitly. Are these laws immanent in the universe? or does it transcend physical reality? In other words, do these laws emerge from the internal properties of the universe as a consequence of its structure or do they pre-exist in an independent conceptual space to which the universe conforms? In this video, I invite you to examine these two major perspectives through the prism of contemporary physics, hence questioning their ontological and epistemological foundation. So, before we begin, it is worth clarifying what we mean by law of the universe. Because contrary to what intuition might suggest, this term covers a reality that is more complex than it appears. In physics, a law refers to a regularity observed in nature expressed in mathematical form. For example, Newton's law of universal gravitation or Maxwell's equations of electromagnetism. These are quantitative, stable, experimentally verifiable relationships that are assumed to be valid at all times and in all places in the universe. Yet a fundamental question arises. Are these laws faithful descriptions of reality or intellectual constructs that reflect our way of modeling the world? Let's take an example. Newton's second law tells us that the resultant force of an object is equal to the product of its mass and its acceleration. This law works remarkably well in a wide range of situations, but it is not true in an absolute sense. It is approximate and limited to a bounded framework and has been surpassed by general relativity and quantum mechanics. This suggests that what we call law may be less an intrinsic property of the world than a conceptual tool forged to account for perceived regularities. In which case, we can distinguish two things. The objective regularities of reality, if they exist, and the scientific laws which are our rational descriptions of these regularities. But if the laws change with the scientific paradigms from Newton to Einstein and then to quantum mechanics, are they really in nature or in our heads? This tension between realism and instrumentalism constitutes one of the foundations of the debate that we are going to explore. And this is where the notions of imence and transcendence take on their full meaning. Immanence implies that the laws of the universe emerge from reality itself. Consequently, it would be inherent in the structure of the universe. It is a naturalistic approach rooted in the materialist tradition. assumes that laws are not imposed from outside, but that they result from the matter of which the universe is made, its symmetries, its physical components, its topology and its dynamics. Let's take the fundamental example of symmetry. Neur's theorem shows us that all laws of physical conservation, energy, momentum, angular motion are linked to a symmetry of space-time. In other words, the laws arise from the geometric properties of the cosmos. They are included in its framework as a logical consequence of its structure. In this view, some laws could even be contingent. If the universe had other properties, other dimensions, other constants, it could obey other laws. This opens the way to hypotheses like the multiverse in which our universe is just one of an infinite number of cosmic bubbles, each governed by a particular set of laws. This vision is also compatible with the idea of emergence. Some laws, such as those of thermodynamics or fluid mechanics, are not fundamental in the strict sense, but emerge from large-scale collective behavior. It is therefore possible that what we today call fundamental law may eventually be reclassified as an emerging law of an even deeper level of description . This immanent approach presents a strong coherence with the epistemology of contemporary sciences. It promotes the idea that science progresses by constructing increasingly efficient models but always rooted in the observation of the world. But this prospect also raises delicate questions. How can we explain the universality of these laws? Why does mathematics describe its regularities so well ? and above all to what extent these laws are really necessary or simply observed. These questions invite us to consider the other great explanatory paradigm, that of transcendence. The laws of the universe may not have originated in the material world itself. From this perspective, the laws of nature would be independent of the particular universe we observe. They would exist in a conceptual, autonomous, abstract, timeless space and the universe would manifest its laws without generating them. Transcendence is found in a certain form of Platonic realism. Laws would be mathematical entities existing in themselves that physicists do not create but that they discover as one explores a pre-existing territory. This is also the position defended in a more structured form by Max Tegmark with his mathematical universe. The universe would not simply be described by mathematics, it would be a mathematical structure. Therefore, laws are not contingent but necessary because they derive from this fundamental structure. More generally, this transcendentalist posture is based on a disturbing question. Why does mathematics, which is a construct of the human mind, allow us to describe the functioning of the universe so precisely? This famous unreasonable efficiency of mathematics, to borrow the expression of the physicist Eugène Wigner, suggests that fundamental laws could belong to an abstract order of reality beyond matter. Here we find an old metaphysical intuition, the idea of a rational order underlying the cosmos that we find among the pre-Soccratics, Plato, but also among modern physicists like Pen Rose who postulate the existence of a world of mathematical form interacting with the physical world and the mental world. But this vision also raises questions. How can an abstract world constrain a physical world? What is the nature of the interface between these two levels of reality? And especially if these laws are transcendental? Why does the universe seem so sensitive to these initial conditions, so fragilely adjusted for these laws to be expressed? In other words, can we really dissociate the laws of the universe from the universe itself? This tension leads us to consider a third way, that of a universe in which the laws would be neither fixed nor absolute, but perhaps evolving. The idea that the laws of the universe could evolve over time was long marginalized. Yet today it finds a growing echo in certain areas of theoretical physics and cosmology. Some cosmological models, such as those of eternal inflation or variable-constant cosmology, suggest that fundamental parameters such as the gravitational constant, the plank constant or the fine-structure constant could have had other values or even fluctuated over time. Furthermore, in approaches such as those of Lis Moline and his evolutionary cosmology, it is proposed that the laws themselves evolve in the manner of a Darwinian process on a cosmic scale. Each universe born from a black hole would inherit a slightly different set of laws selected based on their ability to generate structural complexity. Another possibility is that quantum physics itself could imply a certain plasticity of the laws if these are not fundamental but emerge from an even deeper, still unknown, substrate. These approaches, although speculative, have major epistemological merit. It forces us to abandon the idea of an immutable code and to consider a universe in the making where laws might be local, temporary, and adaptive regularities. But this poses an even more dizzying question. How can we do science in a world where the rules of the game are constantly changing? And this relaunches the initial question in a new light. Are the laws of nature truly fixed once and for all, or are they merely temporary forms of what we have come to recognize as regular? So, are the laws of the universe immanent, transcendent, or evolving ? We have seen that each posture brings its own insight. The immanent approach inscribes laws in the very structure of the universe. It would be emergent properties of reality, contingent depending on the symmetries and initial conditions of our cosmos. The transcendental vision postulates the existence of abstract laws independent of the material world that the universe would come to embody in a Platonic framework where mathematics has a reality of its own. Finally, the evolutionary hypothesis introduces conceptual instability. The laws would neither be given nor fixed, but subject to transformations according to a dynamic that is still poorly understood. These three perspectives are not necessarily exclusive. It is possible and even probable that our current framework of thought is still too limited to fully account for this. Because behind these questions, it is the whole nature of reality that is at stake, as well as our capacity to model it. Basically, our initial question could be reformulated as follows: "Are the laws of the universe ontological entities or epistemological artifacts?" And this reflection brings us back to a fundamental humility, that of the limits of our knowledge, but also to a conviction, the very fact that we can ask these questions with rigor and in itself reveals our ability to think about reality. Are the laws of the universe the necessary reflection of an intrinsic structure of reality or are they the echoes of a mathematical order independent of any materiality? Can they evolve, transform themselves, or are they only local manifestations of a larger system that we are only just beginning to glimpse? What if these laws only reflected at a given moment in our intellectual history our particular way of thinking, of modeling, of seeking meaning in apparent chaos. To what extent is what we call law a property of the world or a construct of the human mind? Faced with this world, the question of the nature of the laws of the universe goes beyond the simple framework of physics to touch on the very foundation of our relationship with reality. Immanent, it would be rooted in the fabric of the universe. Consequence of its internal structure. Transcendent, it would be part of an independent abstract order that the world would manifest without being the source. evolutionary, it would change over time in a cosmic dynamic that is still largely speculative. But perhaps this plurality of vision reflects above all the limits of our models and the blind spots of our understanding? What we call law may be only a transitory reflection of our ability to recognize regularities, a conceptual tool shaped at the crossroads of observation, mathematics and thought. So the real enigma is not only the laws themselves, but what they say or do not say about the profound nature of reality. And what if, ultimately, by questioning the laws of the universe, it simply came down to questioning our own faculty of knowledge. Amen.