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Life, Entropy, and the Search for a Unifying Principle
Introduction
Is there a single physical principle that underlies life’s unique relationship with entropy? Life is often seen as paradoxical in thermodynamic terms: living organisms maintain or even increase their internal order (which in information theory terms means reducing internal Shannon entropy) while simultaneously increasing disorder (classical Boltzmann entropy) in their environment. In other words, organisms build highly organized structures (like cells, tissues, DNA sequences) even as they dump waste heat and metabolites to the outside world, raising the overall entropy of their surroundings. This apparent two-way manipulation of entropy — gathering information and order internally, expelling chaos externally — raises a profound question: Could it be governed by a unifying physical law? And might the emergence of life be as predictable as a phase transition in a thermodynamic system? To explore this, we must synthesize insights from nonequilibrium physics, information theory, origin-of-life research, and even philosophy. We will examine cutting-edge ideas, from Jeremy England’s theory of “dissipative adaptation” to Landauer’s limit linking information and heat, and Karl Friston’s free energy principle from neuroscience. Along the way, we will consider whether life’s rise is an inevitable outcome of the right conditions – a kind of thermodynamic phase transition – or a remarkable coincidence. By the end, we hope to see whether a clearer picture emerges of life’s role in the grand thermodynamic story of the universe.
The Entropy Paradox of Life
The second law of thermodynamics tells us that in a closed system, entropy (disorder) inexorably increases. Left alone, hot coffee will cool to room temperature, and eggs will scramble but never un-scramble – there are simply far more ways for things to be jumbled than orderly. Yet living systems seem to buck this trend locally. As early as 1944, physicist Erwin Schrödinger highlighted this puzzle in his book What Is Life?, coining the term “negative entropy” (or negentropy) to describe what life feeds on. An open system like an organism can maintain or decrease its internal entropy by exporting entropy to its environment. For example, a green plant absorbs highly ordered, low-entropy sunlight and uses that energy to assemble sugars and complex structures; in doing so it emits infrared radiation and waste heat, thereby increasing the entropy of its surroundings. In this way, the overall entropy of the universe still rises (the second law is safe), even as the plant maintains an island of order within itself. Schrödinger’s insight was that living things survive by sucking orderliness from their environment (in the form of free energy) and ejecting disorder back. In modern terms, life constantly imports free energy (usable energy) and exports entropy (unusable energy) to keep its own internal structures intact.
Crucially, this process doesn’t violate thermodynamics – it exploits it. Living organisms are open systems: they continually exchange energy and matter with the environment. The Earth itself is an open system, bathing in sunlight and radiating heat to space. As a result, local pockets of decreasing entropy can appear, as long as they are offset by greater entropy increases elsewhere. A household refrigerator provides a mundane analogy: it pumps heat out of its interior (making the inside more ordered and cold, i.e. lower entropy) but releases that heat into the kitchen, increasing the entropy of the room. Life similarly acts like nature’s refrigerator – constantly expending energy to preserve internal order at the cost of greater disorder expelled externally. In fact, some researchers argue that one of life’s primary thermodynamic functions is precisely to accelerate entropy production in its environment. For instance, early biochemical pathways on Earth (like photosynthesis using pigments) may have arisen because they increased the overall dissipation of the solar energy reaching the planet. According to this view, the biosphere exists (in part) to help transform incoming low-entropy energy (sunlight) into high-entropy forms (heat) as efficiently as possible.
This perspective reframes the old question “Does life defy entropy?” into “How does life use entropy?” Rather than being an exception to the second law, life may be a consequence of it – an exquisite strategy for hastening the universe’s slide toward thermodynamic equilibrium. But is there a rigorous principle describing this strategy? Modern developments in physics and information theory hint that there might be.
Self-Organization and Dissipative Structures
In the mid-20th century, scientists like Ilya Prigogine began to tackle the challenge of nonequilibrium thermodynamics – the study of systems that are actively driven by external energy and exist far from thermal equilibrium. Prigogine introduced the concept of dissipative structures: ordered patterns that emerge in open systems dissipating energy. A classic example is the formation of convection cells (Bénard cells) when a fluid is heated from below – once the temperature difference crosses a threshold, an organized hexagonal pattern of circulating currents spontaneously appears, increasing the dissipation of heat. This is a kind of phase transition in a driven system: a new form of organization “crystallizes” out of disorder when conditions are right.
Life can be viewed as the ultimate dissipative structure. It arises in environments with a constant throughput of energy (sunlight, chemical gradients, etc.) and uses that flow to build and maintain structure. Far from equilibrium, living systems constantly produce entropy as they metabolize, but in doing so they self-organize into complex forms. In the 1960s and 70s, Prigogine and others showed that under far-from-equilibrium conditions, systems can undergo sudden shifts to more ordered states that dissipate energy more effectively – in essence, order through fluctuations. This invites an enticing analogy: perhaps the origin of life was a kind of thermodynamic phase transition – a predictable transformation of an energy-driven chemical soup into an organized, self-replicating system once a critical threshold was crossed.
Some contemporary thinkers have indeed described the emergence of life in such terms. For example, one approach frames the origin of life as a symmetry-breaking phase transition in which a new form of order (the “biological” phase) appears. Specifically, life introduced a novel kind of symmetry – the arbitrary encoding of information (e.g. genetic code) – that broke the symmetry of the inanimate world. In this view, as simple chemical systems became more complex, there came a tipping point where matter started to store and process information in a symbolic way (like sequences of nucleotides representing genes) – a fundamental shift akin to water freezing into ice, but in the informational realm. While this idea is still speculative, it treats life’s origin as arising from general physical principles, not accident. If we can identify an “order parameter” (such as the amount of information stored, or the degree of self-catalysis in a chemical network) that suddenly ramps up at a certain energy throughput or concentration, that would strongly suggest a phase transition mechanism at work.
Even without invoking new laws, we know that self-organization happens in nonliving systems. Snowflakes form intricate symmetric crystals as water molecules spontaneously order themselves while releasing heat to the environment. Sand dunes organize into regular waves under the constant driving of wind. Importantly, these structures form because they are good at dissipating the energy flowing through the system. A sand dune array allows wind to lose energy via friction in a patterned way; a snowflake’s form emerges from the release of latent heat during freezing. Life takes it a step further by not only self-organizing passively (like a snowflake) but by actively maintaining and propagating its order (through metabolism and reproduction). But the continuum is clear: nature has many examples of order emerging from disorder in open systems. The big question is whether life’s brand of order – self-maintaining, information-rich, and adaptive – is just a higher-order example of the same thermodynamic tendency, describable by an overarching principle.
Information, Entropy, and Landauer’s Principle
To dig deeper into life’s entropy trick, we must consider information theory. Claude Shannon’s definition of information entropy (often just Shannon entropy) measures the uncertainty or randomness in a set of messages or arrangements. Interestingly, Shannon’s entropy has the same mathematical form as the entropy in statistical physics (the Boltzmann–Gibbs entropy); they differ mainly in interpretation and units. In simple terms, a highly ordered state (like a neatly arranged deck of cards or the DNA sequence in a cell) has low information entropy because there are relatively few ways to arrange the parts and still get that exact order. A random state (shuffled cards, or random polymer sequences) has high entropy because it could be any of a huge number of configurations. Life typically occupies extremely particular states (e.g. a human genome is one incredibly specific sequence out of an astronomically large space of possibilities) – that specificity means living systems have lower Shannon entropy than a random mishmash of the same components. In effect, organisms “know” a lot about their environment (through their DNA, structures, and learned behaviors), which is another way of saying they have accumulated information and reduced uncertainty internally.
However, acquiring and maintaining this information comes at an energetic price. This is where Landauer’s principle enters the story. Rolf Landauer in 1961 argued that information is physical – that logically irreversible operations, like erasing a bit, have unavoidable thermodynamic costs. Landauer’s principle sets a lower bound on the energy required to erase one bit of information: at minimum, erasing a single bit dissipates an energy of $k_{B}T \ln 2$ as heat (here $k_{B}$ is Boltzmann’s constant and $T$ is the temperature of the environment). In other words, whenever a piece of information is erased or irrevocably overwritten, the entropy of the environment must increase by at least a tiny amount (on the order of $k_{B}\ln 2$ per bit). This profound result bridges information theory and thermodynamics: it tells us that manipulating information has an entropy cost. There is no free lunch for Maxwell’s demon – if a clever being (or device) sorts fast molecules from slow ones to decrease entropy, it must pay by increasing entropy elsewhere, for instance when it erases its memory of past measurements.
For living organisms, Landauer’s principle is highly relevant. Consider that every biological process which stores or deletes information – copying DNA, proofreading and repairing genetic code, breaking down misfolded proteins, or even a neuron “resetting” after firing – must obey this principle. Life is sometimes analogized to a natural Maxwell’s demon: it continuously gathers information about its environment (sensing nutrients, threats, etc.) and uses that information to perform work (moving, growing, reproducing). But Landauer’s insight assures us that any such information-processing must dissipate heat. A bacterium swimming up a nutrient gradient, for example, is effectively “measuring” the concentration difference and storing that information in its molecular circuits; when those circuits reset or when the cell divides and “forgets” some prior state, a Landauer heat cost will be paid. The more information an organism handles, the more minimal heat it must, in principle, release. In short, reducing internal Shannon entropy inevitably creates external Boltzmann entropy – exactly the trade-off we see with life. Modern experiments have even verified Landauer’s limit on tiny scales, showing that bit erasure indeed dissipates the predicted amount of heat, validating this bedrock principle of the thermodynamics of information.
What this means for a unifying principle is that any proposed law governing life’s entropy trick must respect the information-entropy link. If an organism becomes more ordered (information-rich), it must be offset by environmental entropy gains. Landauer’s principle provides the quantitative book-keeping for that exchange. It also suggests why living systems often appear to operate near thermodynamic efficiency limits. Indeed, one analysis found that the minimum thermodynamic cost for a simple organism (or replicating molecule) to reproduce is very close to the actual heat dissipated by real cells during replication. Life, evolved by natural selection, has likely come close to these physical limits in many cases – any unnecessary waste of energy would be weeded out, especially at microscopic scales. This hints that a unifying principle might say something like: living systems optimize the trade-off between information gain and entropy production, operating near the limits set by fundamental physics. Landauer’s principle would be a key component of such a framework, ensuring the books balance between bits and heat.
Dissipation-Driven Adaptation: Jeremy England’s Theory
Can the emergence of life itself be explained by a tendency of matter to self-organize in order to dissipate energy? In recent years, physicist Jeremy England proposed what he calls dissipation-driven adaptation – a provocative hypothesis that tries to put life’s origin on a purely physical footing. According to England’s theory, when a group of particles is driven by an external energy source and is able to dump waste heat into its surroundings (much like an open system in nature), it will statistically tend to rearrange itself over time into states that dissipate the incoming energy more efficiently. In plain terms, if you shake a bunch of atoms or molecules with some energy source (be it mechanical vibration, electromagnetic waves, chemical fuel, etc.), they won’t just wander randomly forever. Given the right conditions, they are more likely to stumble into structures that absorb and disperse the energy influx better – and once they do, those structures will persist (since they’re better at handling the driving force). This idea is a bit like survival of the fittest, but with the “fittest” defined by physics: the structures that survive are those that dissipate energy the most.
England has put numbers to this. He derived a generalized second law for driven systems and showed that evolutionary-like outcomes are most likely to be those that dump more heat into their environment on the way to forming. One striking result was his calculation of the minimum entropy production (or heat dissipation) required for a simple self-replicator to make a copy of itself, such as an RNA molecule. He found that actual biological systems (like E. coli bacteria or RNA replicators) operate not far from these minimal dissipation values. In other words, life’s basic process of replication appears to be remarkably efficient in thermodynamic terms, almost as if evolution has driven it to meet a physical bound. England quips, “A great way of dissipating more is to make more copies of yourself” – a colorful way to say that replication is a powerful strategy to spread out energy (since more copies mean more total surface or volume to absorb energy and more metabolic activity to turn that energy into heat).
Under England’s hypothesis, even inanimate matter can “adapt” in this way. We don’t need DNA or natural selection at the start – those may simply refine a process that physics started. For example, experiments have shown that certain systems of colloidal particles, when driven by an oscillating energy source, will spontaneously form bonded structures that then template the formation of similar structures nearby. In one case, plastic microspheres coated with specific molecules assembled into clusters, and those clusters induced neighboring free spheres to join and form identical clusters, effectively self-replication – all driven by the release of chemical energy in the system. No “genetic program” was telling these colloids to copy themselves; the process was guided by the thermodynamic advantage of the new structure under the driving conditions.
Above: An illustration of a self-replicating cluster of microspheres (red) that forms in a driven chemical system and induces free particles (blue) to assemble into an identical cluster. Such experiments demonstrate that nonliving matter can spontaneously develop lifelike organization when energy is supplied. This supports the idea that dissipative structures can “adapt” to better dissipate energy, potentially seeding the emergence of life.
England’s theory suggests a unifying principle along these lines: matter tends to organize and reproduce in forms that maximize entropy production in their environment. If true, life is just the pinnacle of a spectrum of dissipative structures. Snowflakes, sand dunes, convection cells, even Jupiter’s Great Red Spot could all fit under this broad tent of dissipation-driven organization. What makes life special is that it inherits and refines these physical tendencies via evolution – DNA and natural selection ride atop the deeper thermodynamic imperative to dissipate energy. Not everyone is convinced; England’s ideas are still being tested and debated, with some arguing they are still too speculative. But they are attractive in that they promise to demystify life’s origin. If a puddle of chemicals, given a steady energy supply, will almost inevitably boot up some self-organizing, replicating reactions (because those reactions just happen to be great at converting free energy into entropy), then life might not be a freak accident at all, but rather “written into” the laws of physics.
The Free Energy Principle: Life as Minimization of Surprise
Another ambitious attempt at a unifying framework comes from neuroscience and theoretical biology, in the form of Karl Friston’s free energy principle. Friston’s work originated in trying to explain how the brain works, but it has expanded into a grand philosophical theory of life itself. In essence, the free energy principle posits that living systems maintain their order and integrity by minimizing something called “free energy,” which in this context is closely related to surprise or prediction error. In everyday language, it says: organisms must minimize the gap between what they expect to experience and what they actually sense. If they don’t, they will be persistently surprised by their environment, which means they’re failing to capture regularities and will eventually be overwhelmed by unexpected perturbations (in other words, succumb to disorder).
Friston often explains this in terms of surprise = entropy. If you’re constantly surprised by what’s happening (imagine an animal repeatedly encountering completely unpredictable situations), that essentially means you have high uncertainty about the world – high information entropy in your understanding of the environment. Life can’t persist in that state; a creature that has no internal model of its world would quickly get into lethal trouble. Thus, Friston argues, surviving organisms must manage to keep “surprise” (on average) low. They do so in two ways: perceptually, by updating their internal mental/physiological models to better predict what’s out there, and behaviorally, by taking actions that make the environment more like what they expect (seeking comfort zones, avoiding shocks). The free energy principle formalizes this as a kind of Bayesian feedback loop – it’s as if each organism is constantly doing statistical inference to minimize the difference between its predictions and incoming sensory data, thereby minimizing its variational free energy (a measure of that difference).
This might sound abstract, but an example can help. Imagine a simple thermostat in your home set to 22°C. If the room’s temperature deviates from that, the thermostat senses the change (surprise) and triggers the heater or AC to bring the temperature back – effectively making reality conform to its “expectation” of 22°C. In Friston’s view, a living body is analogous: your brain/body has expectations (like a preferred range of temperatures, or blood sugar levels) and will act to correct deviations (shivering, sweating, seeking food). As Friston puts it, if a thermostat had beliefs it might say, “My world is supposed to be 22°C,” so anything different is surprising and it will work to remove that surprise. In doing so, it is minimizing entropy, since in the long run, surprise equates to entropy in the organism’s experience.
Friston’s principle is sometimes summarized as “life is resistance to entropy.” One Nautilus article caption described it neatly: lifeforms, to survive, “must limit the long-term average of surprise they experience in their sensory exchanges with the world. Being surprised too often is tantamount to a failure to resist a natural tendency toward disorder.”. In other words, organisms avoid being constantly buffeted by chaos (disorder/entropy) by making and updating internal models of the world. Those models allow them to anticipate and thus mitigate the constant drift toward entropy. The free energy principle ties together ideas from neuroscience (perception as inference), evolution (organisms that fail to reduce surprise will be selected against), and even physics (it has parallels to principles of least action and minimum free energy in thermodynamics).
While Friston’s framework is mathematically intricate, conceptually it aligns with our entropy story: life is informational and predictive. An organism embodies a model of its niche (encoded in its brain, DNA, etc.), which is a compressed description of the predictable aspects of the world. By leveraging this information, the organism keeps itself in a low-entropy state (homeostasis) despite external perturbations. If it couldn’t, it would dissolve into the environment (death, decay – a return to high entropy). Some researchers are excited about the free energy principle as a candidate for a true unifying theory of life’s dynamics; others are skeptical, noting it can become almost tautologically broad (“everything is free energy minimization”). Nevertheless, it provides a powerful narrative that complements the others we’ve discussed: life as a process of actively carving out order (low entropy) by continuously learning about and shaping its environment.
Speculations: A Predictable Phase Transition to Life?
Taking these ideas together, we can’t help but ask: If life indeed follows general physical principles (whether maximizing entropy production, minimizing free energy, or some combination thereof), does that mean life had to arise given the right conditions? Is life an inevitable outcome of certain environments, rather than a cosmic fluke? This is a hot topic weaving together science and philosophy. On one hand, the traditional view (famously espoused by Jacques Monod) is that life’s emergence was a highly contingent event – essentially a lucky roll of the chemical dice. On the other hand, thinkers like Stuart Kauffman and others in complexity science have long suggested that self-organization and increasing complexity might be built into the fabric of the universe, tilting the odds in life’s favor when conditions permit.
Recent work by some astrobiologists and Earth scientists leans toward the latter view. In 2021, Robert Hazen and Michael Wong, among others, proposed what amounts to a new law of nature: a law of increasing complexification. They argue that as the universe ages, the complexity of structures within it tends to grow, not just in biology but in geology, chemistry, and technology – and that this increase in organized complexity could be as fundamental as the increase in entropy. If true, then the rise of life (and even intelligence) might be statistically likely wherever there is a sustained source of energy and the opportunity for information to accumulate. In their view, Darwinian evolution on Earth is just a special case of this broader cosmic tendency – a local instance where chemistry, under solar energy, organized into self-preserving, reproducing systems. The principle they outline suggests that entities (whether molecules, minerals, or organisms) are naturally “selected” because they carry more functional information – that is, they perform some function that helps dissipate energy or utilize resources, thereby sticking around longer. Over time, this biases the world toward more complex, function-rich forms.
This perspective is admittedly speculative and not universally accepted. It essentially adds a dash of teleology (purposefulness) to physics – implying the universe has a built-in drive to create complexity and life. Critics point out that we must be careful: the second law of thermodynamics remains paramount, and any pockets of complexity must be paid for by greater entropy elsewhere (which, as we’ve described, life certainly does). The question is whether the second law itself implies an increase in complexity under the right circumstances. Some argue that maximizing entropy production (MEP) principles cause systems to find whichever configuration dissipates energy fastest, which often means more complex, structured behavior. Earth’s biosphere, for instance, might have emerged because an ecosystem of organisms dissipates solar energy faster (via photosynthesis, respiration, etc.) than bare rock and ocean would on their own. If that’s the case, life on Earth might not be a random stroke of luck at all, but rather a thermodynamic inevitability once the young Earth’s oceans and atmosphere started receiving a steady flux of sunlight.
Is there a way to test these ideas? Researchers are attempting to develop mathematical models that treat the origin of life as a phase transition – complete with order parameters and critical thresholds. They’re searching for measurable signals, such as abrupt changes in chemical complexity or energy flows, that would indicate a self-organizing transition took place. If life’s emergence is like water freezing or a magnet magnetizing (albeit in a far-from-equilibrium setting), there should be telltale signatures: e.g., a sudden drop in entropy of the system coupled with a spike in entropy production rate externally, or the appearance of long-range correlations between molecules (signaling the onset of organization). Experiments are also probing these questions. In laboratory simulations of early-Earth environments – say pools of reactive chemicals with light or heat as input – scientists are watching for spontaneous increases in order or even rudimentary “proto-life” behaviors. Jeremy England’s ideas are inspiring some of these experiments, aiming to see if random chemical systems can indeed learn to dissipate energy better over time. Additionally, as we explore other planets and moons, our discoveries (or non-discoveries) of life will inform this debate. If life pops up readily in diverse places (Mars, Europa, Enceladus, exoplanets), it would strongly support the inevitability camp. If it appears to be extremely rare, then perhaps a lot of things had to line up just so on Earth.
From a philosophy of science standpoint, the hunt for a unifying principle of life’s entropy behavior touches on deep issues. It challenges the divide between life and non-life, suggesting a continuity governed by physics. It also forces us to consider what counts as a “law” of nature. Are Darwin’s evolution by natural selection or the proposed complexity principle comparable to, say, the laws of thermodynamics? Some think we may be observing an emergent law – one that isn’t visible at the level of fundamental particles but emerges statistically at higher levels of organization (much like how the ideal gas law is an emergent rule from many molecules). Others caution that we might be anthropomorphizing the universe – seeing purpose where there is none, or extrapolating from a sample size of one (life on Earth) to the whole cosmos. The dialogue between these perspectives is valuable because it helps refine our hypotheses and encourages interdisciplinary research. Whether or not life is “written into” the universe, studying it through the lens of entropy and information has already yielded practical insights (for example, understanding the efficiency of molecular machines, the limits of computation in cells, and new approaches in artificial life and AI based on free energy minimization).
Conclusion
The interplay of life, entropy, and information is undoubtedly complex, but it need not be mystifying. As we’ve explored, multiple lines of thought are converging on the idea that living systems follow from the same physics that governs nonliving matter – just in a more elaborate, information-rich way. Jeremy England’s work proposes that the basic ingredients of life might naturally organize to dissipate energy better, implying a physical drive behind biogenesis. Landauer’s principle reminds us that information is physical and that life’s information processing is bounded by thermodynamic costs – life cannot cheat the second law, it can only strike deals with it. Karl Friston’s free energy principle offers a unifying view that life is always busy reducing the uncertainty (entropy) it faces by building models and predicting the world. All these ideas reinforce a picture of life as part of the natural order, not an outsider. If there is a single unifying principle emerging, it might be phrased like this: Life is the process by which energy-driven systems locally reduce their information entropy (create order and knowledge) by increasing the thermodynamic entropy of their surroundings, in such a way that this self-organization becomes self-preserving and self-replicating. This could be seen as a kind of thermodynamic imperative, or an inevitable phase transition, under the right conditions of energy flow and complexity.
Of course, much remains to be discovered. Whether life is truly an inevitable outcome of physics – as inevitable as ice forming when water freezes – is still an open question. We have only one known example of life, and it’s possible that chance still played a role in how the details unfolded. But the fact that we can even pose life’s emergence as a physics problem is a triumph of interdisciplinary science. It means we are inching closer to demystifying life’s place in the universe. If a unifying physical principle of life exists, its implications would be profound: it would suggest we are not outsiders to the cosmic story, but rather a natural expression of it, driven by the same thermodynamic winds that shape stars, snowflakes, and sand dunes. And perhaps most excitingly, it would hint that life – in some form – could be abundant throughout the cosmos wherever conditions favor that thermodynamic dance of order and entropy. Finding that principle, if it’s out there, will require continued synthesis of theory and experiment, and a willingness to blur the boundaries between physics, biology, and information science. The question of life’s entropy juggling act cuts to the heart of what life is, and by understanding it, we edge closer to understanding ourselves and our inevitable place in the universe’s unfolding.
Sources: The discussion draws upon theoretical and experimental insights from physics and biology, including Schrödinger’s concept of “negative entropy”, Prigogine’s dissipative structures, and recent proposals by researchers. Jeremy England’s dissipation-driven adaptation hypothesis suggests that matter self-organizes to dissipate more energy, potentially explaining life’s emergence as a physical process. Landauer’s principle establishes the link between information entropy and thermodynamic cost, ensuring life’s information gains are paid for in heat. Karl Friston’s free energy principle interprets life as minimizing surprise (entropy) through predictive modeling. Further, proposals by Hazen, Wong, and colleagues posit a new law of increasing complexity, making life a likely outcome of cosmic evolution. These perspectives, while still being tested, collectively advance the idea that life’s reduction of internal entropy at the expense of external entropy obeys knowable laws – potentially describable as a thermodynamic phase transition – rather than being a mere accident of chemistry. The coming years of research will tell us how far this unifying principle can be formulated mathematically and validated empirically. But even now, the convergence of ideas from multiple fields is a promising sign that we are honing in on the answer to why life must do what it does, and perhaps, why life must happen at all.
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