Design in Nature: How the Constructal Law Governs Evolution in Biology, Physics, Technology, and Social Organization

by Adrian Bejan

In this groundbreaking book, Adrian Bejan takes the recurring patterns in nature--trees, tributaries, air passages, neural networks, and lightning bolts--and reveals how a single principle of physics, the Constructal Law, accounts for the evolution of these and all other designs in our world.
Everything--from biological life to inanimate systems--generates shape and structure and "evolves" in a sequence of ever-improving designs in order to facilitate flow. River basins, cardiovascular systems, and bolts of lightning are very efficient flow systems to move a current--of water, blood, or electricity. Likewise, the more complex architecture of animals evolve to cover greater distance per unit of useful energy, or increase their flow across the land. Such designs also appear in human organizations, like the hierarchical "flowcharts" or reporting structures in corporations and political bodies.
All are governed by the same principle, known as the Constructal Law, and configure and reconfigure themselves over time to flow more efficiently. Written in an easy style that achieves clarity without sacrificing complexity, "Design in Nature" is a paradigm-shifting book that will fundamentally transform our understanding of the world around us.

Genres: Science, Physics, Nonfiction, Design, Nature, Evolution, Biology

306 pages, Kindle Edition

First published January 24, 2012

About the author

Adrian Bejan (MIT, 1971, 1972, 1975) is an American professor and discoverer of the constructal law of design evolution in nature. He is J. A. Jones Distinguished Professor at Duke University. He published more than 620 articles, 29 books and is in top 100 of most cited engineers in the world. He is a member of the Academy of Europe, and received 18 honorary doctorates from universities in 11 countries.

Academy of Europe:
http://www.ae-info.org/ae/User/Bejan_...

Constructal Law: Astrobiology Magazine
http://www.astrobio.net/topic/solar-s...

Reviews

[Mircea Petcu · Rating 5 out of 5]

Universul, rețeaua hidrografică, frunzele, oasele și traficul urban au o structură asemănătoare. Am observat asta. Totuși, nu m-am gândit că există o lege care le unește, numită lege constructală, și o știintă care o studiază, numită termodinamică constructală.

Am reținut că ”societatea devine din ce în ce mai ierarhizată pe măsură ce mișcarea membrilor crește.”. Inegalitatea în societate este înscrisă în legea constructală. Karl Marx este învins de fizică.

E o carte foarte interesantă care îți schimbă modul de a vedea lumea.

[David Rubenstein · Rating 2 out of 5]

In this book, Adrian Bejan hypothesizes a principle that he names the "constructal law". It states that everything in nature configures itself and reconfigures itself to increase flow, or to make flow more efficient.

What does Bejan mean by flow? Any concrete object or abstract concept can flow. Water can flow, air can flow, blood, heat and electricity can flow. Also, knowledge, concepts, memes, ideas, and data are things that flow.

By "design", Bejan does not mean that somebody designed the flows. He means that the flows configure themselves into a design.

A prime example of the constructal law is the flow of rainwater. It falls everywhere, and drops of water coagulate into millions of branchlets, which combine into thousands of tiny streams, hundreds of large streams, creaks, and a smaller number of rivers. This hierarchy is "designed" to maximize the flow of water. The circulatory system in animals and humans is similarly configured into capillaries, small and large arteries. The trunk of a tree is divided into a few stout branches, more thin branches, and many very thin branches and then to leaves, a structure that helps to maximize the flow of water through the tree and into the atmosphere.

A road system starts out with lots of narrow dirt roads, fewer paved side roads, fewer major roads, and fewer main highways. This system maximizes the flow of traffic. The diffusion of knowledge follows a similar pattern, as does the flow of athleticism through high schools, colleges, and on into professional sports.

Bejan uses mathematical formulas to back up his claims that these designs help to maximize the various flows in nature.

But I have a few complaints about the book. First, it is very repetitive. This type of book, where a major claim of a new idea is made, seems to fit a pattern where the author self-aggrandizes the importance of his new idea or theory.

I always thought that the "purpose" of an organism is to reproduce its own genes. But Bejan claims that the purpose of all organisms is to maximize flow. The purpose of a tree, for example, is to maximize the flow of water from the ground into the atmosphere. The purpose of a fish is to undulate and churn the water in the ocean, to mix it and to make it flow more rapidly. This seems so bizarre to me.

Many things in nature organize themselves by some power law. The book is filled with graphics that demonstrate these power laws over a diverse variety of "flows". Bejan claims that this is evidence in favor of the constructal law. He claims that the constructal law is a law of physics, but when he claims that the fact that the frequency of words in language obeys a power law is evidence of a law of physics, I have a hard time agreeing.

There is a core of genius in the constructal law. But it is buried in some tedious, repetitive language. Perhaps the author could clean it up. At the same time, he could demonstrate not only what but also how these structures configure themselves to obey the constructal law.

[Michiel · Rating 2 out of 5]

Like some people before me, I was was somewhat disappointed in this book.

First of all, Bejan is very arrogant. He is not the first, nor will be the last popular science author to be this, but it quite insufferable of him to keep repeating that he has surpassed Darwin and can make every (important) thing in nature clear by performing his subfield of thermodynamics. Of course prof. Bejan keeps reminding us that it is only natural that the ignorant masses can't recognize his genius. (And he doesn't like Communism).

The so-called constructal law is extremely vage. Design in nature arises to maximizes a 'flow'. What kind of flow? Would it prefer a flow of 100 l of water per second or of 100 l of air? Is there some theoretical derivation of this law, based on the laws of thermodynamics? Why don't I know this if I have read the book?

No formal discription of the law is given. Every chapter contains a couple of (rather badly structured) examples. Though some of them are quite interesting, I fail to see any need for any constructal low. Trees are tree-shaped because they need to keep a flow of water (to transport nutrients, keep their cells turgid and keep their floem moving). This could be predicted by the principles of evolution, same for the animals' movement.

In short, this book could be really interesting but should have been better (and more critically!) edited.

[Manuel Alfonseca · Rating 1 out of 5]

ENGLISH: This book is presented as groundbreaking, when in fact it's just a question of renaming. What he explains here is almost the same thing as Benoit Mandelbrot described in his fractal theory of 1977 (35 years before this book). His "constructal law" is nothing other than the growing of a fractal.

However, and this is something that Mandelbrot didn't do, the authors make clear their atheism, as when they say design without an intelligent designer. How do they know that there is no intelligent designer? Of course, they come with that idea as a starting point or axiom (God does not exist) and then believe that they have deduced it from their reasoning, when it's precisely the other way around. This is typical of atheists.

They also say things like these: The unifying definition marks an advance because it removes the concept of life from the specialized domain of biology. But nothing in the book explains "life," it just describes ways in which life develops, just as Mandelbrot did decades before. And saying that the fact that life uses the same paths of development as rivers (for instance) is not more novel than the assertion that all life is based on atoms and molecules, just like rivers.

The book is written as the gospel of a new theory. The problem is that neither the theory is new, nor is the reasoning convincing, because it tries to draw too many consequences from a previously known fact, which the authors turn into the key to everything.

This book is quite typical of our times: it purports to discover the Mediterranean by offering a single law that explains everything. Somewhat similar to Stephen Wolfram, who says he can explain the universe by means of cellular automata. We are strongly interested in trying to explain everything by means of a simple variable, or rule, or law, as in this case. But see this post in my blog: Dostoyevsky and the function of one variable.

ESPAÑOL: Este libro se presenta como innovador, cuando en realidad se limita a cambiar nombres. Lo que explica aquí es casi lo mismo que describió Benoit Mandelbrot en su teoría fractal de 1977 (35 años antes que este libro). Su "ley de construcción" no es otra cosa que el crecimiento de un fractal.

Sin embargo, y esto es algo que Mandelbrot no hizo, los autores dejan claro su ateísmo cuando dicen diseño sin diseñador inteligente. ¿Cómo saben que no hay diseñador inteligente? Claro, parten de una idea inicial o axioma (Dios no existe) y luego creen que lo han deducido de su razonamiento, cuando es precisamente al revés. Esto es muy corriente entre los ateos.

También dicen cosas como estas: Nuestra definición unificadora marca un avance, porque saca el concepto de la vida del dominio especializado de la biología. Pero nada en el libro explica la "vida", sólo describe formas en que la vida se desarrolla, tal como lo hizo Mandelbrot décadas antes. Y decir que el hecho de que la vida utiliza los mismos caminos de desarrollo que los ríos (por ejemplo) no es más novedoso que afirmar que toda vida se basa en átomos y moléculas, igual que los ríos.

El libro está escrito como si fuera el evangelio de una nueva teoría. El problema es que, ni la teoría es nueva, ni el razonamiento es convincente, porque trata de sacar demasiadas consecuencias de un hecho conocido previamente, que los autores convierten en la clave de todo.

Este libro es bastante típico de nuestro tiempo: pretende descubrir el Mediterráneo ofreciendo una ley única que lo explica todo. Algo parecido a Stephen Wolfram, quien pretende explicar el universo mediante autómatas celulares. Estamos muy interesados en explicarlo todo mediante una sola variable, o regla, o ley, como en este caso. Pero lean este artículo de mi blog: Dostoievski y la función de una sola variable.

[Katherine · Rating 3 out of 5]

Design in Nature presents some interesting new thoughts on flow systems and the nature of the biosphere. However, I don't think it really achieves its purpose of introducing these thoughts to a lay audience.

Note: I was an English major. If you are a scientist or a mathematician, you may well get a lot more out of it than I did.

The primary author is Adrian Bejan, who is a well-known physics professor at Duke University. His cowriter is J. Peder Zane, whom I assume was hired to make the book more accessible. Both authors were at a signing I attended back in February, and I really enjoyed their presentation. However, in retrospect I think that Dr. Bejan is probably better at presenting his ideas in person than in writing them down.

From my reading of the book, I took away the following:

1) That every flow system must sustain itself by evolving into the most efficient possible structure;
2) That the vascular structure (veins, lightning bolts, etc.) is the most efficient;
3) That Earth's biosphere is itself a flow system, and that the underlying purpose of evolution is to transfer biomass more efficiently over the Earth's surface.

The last chapter expands on these ideas in interesting ways. It is here, for example, that Dr. Bejan explains his idea of the "human and machine species"--that is, that humanity should be considered to include all the machines and transfer systems it uses to move its goods and services from place to place. I got the impression that this last chapter was actually the point of the whole book. The first nine chapters were probably intended to introduce the concepts needed to understand the idea of the "human and machine species." However, I'm pretty sure that a lot of people must have put this book down without getting anywhere near the end of the ninth chapter.

I really enjoyed the book at first. It was a little hard to follow--Dr. Bejan is not a native English speaker, and so his sentence structures are uniformly awkward. As I went on, I began to feel that the book was also rather repetitive; short as it is, condensing it would have made it much clearer. The text also includes a number of scientific formulas, which were more or less Greek to me. Since I got the impression that Design in Nature was intended for lay readers, it probably would have been better to put the formulas in an appendix, or in footnotes, as in Brian Greene's books about the cosmos. I would really like to know more about math and physics than I do, and was embarrassed to have so much trouble following these formulas. However, as Design in Nature is not an introductory textbook, the inclusion of formulas will probably just confuse most lay readers.

The images were another weakness. The simple line charts were fine, and did add a lot to the text, but the grainy black-and-white photographs were mostly just disappointing. Several of the diagrams were almost nonsensical. Considering how much money must have gone into the slick, engaging cover, you'd think that Doubleday could have splurged on a few good graphics.

Oddly, Design in Nature felt like a philosophical treatise as well as a physics book. There were a lot of little comments about how the whole world is an interconnected system, and the whole "human and machine species" thing would have gone well in a science fiction book. Since these are pretty broad, sweeping statements, though, I would have preferred for the author to lay out a neat explanation of his fundamental concepts, then expand into philosophy. The whole idea of nature "designing" itself gave certain passages a New Age-y feel, and though Bejan makes it clear that he's not talking about anything religious or spiritual here, he frequently expressed himself in ways that made him seem a bit less credible.

Overall, I thought that this book had a lot of potential, but I don't really feel that it delivered on its intentions. It probably would have done well with a complete rewrite, possibly with a different cowriter (since this one seems to have done nothing to make Bejan's strange phrases more intelligible). However, I got through it, and it gave me a lot to think about.

[Chip Hunter · Rating 1 out of 5]

I picked up this new book prepared to be disappointed. A unifying principle of everything that evolves!! A brand new scientific LAW!! With claims like these, surely there would be some acknowledged limitations or boundaries for application of this theory. Not at all. Instead of carefully ushering their supposedly unique idea into the mainstream of scientific and engineering thought, the authors use this book as a bludgeon to sell their "law", making such grand claims and proclamations as to be ridiculous. Indeed, the incredulity with which I read this book never ceased. The authors somehow continued to up the ante, their claims becoming more and more grand from chapter to chapter.

The Constructal Law basically says that things change to become more efficient. Both living and non-living things evolve in predictable ways over time. Rivers change to move water efficiently, animals evolve to compete and survive and breed more effectively, human designs change over time to work more smoothly and efficiently. Basically, the Constructal Law is nothing more than a reduction of the laws of Thermodynamics along with an outline of what we all intuitively know. Bejan wants to make the case that his Law can help guide scientists and engineers in designing their experiments and machines. In the introduction of the book, he paints a picture of past scientists and engineers helplessly bumbling around without the guiding light of his Constructal Law. I can appreciate a person trying to convince his audience of his views, but these attempts come off as the most extreme sort of arrogance, and really distract from the central point.

If the authors could have stayed in bounds, and limited their ideas to the original intentions, this book could have been decent. The Constructal Law can predict shape and size of many natural and man-made objects, from river basins to the architecture of tree branches to highway layouts in busy cities. These parts of the book were interesting and made sense. Unfortunately, the authors couldn't restrain themselves from taking it to the next level. Much of the book was dedicated to convincing the reader that the Constructal Law provides the missing link for "proof of the unification of the oneness of nature." The authors argue that life itself has evolved principally as a mechanism for moving matter around the earth. They view trees as having evolved as machines for moving water from the earth to the atmosphere. Animals as machines for moving matter through the oceans and over the land. These are radically backwards from the more traditional views of evolution, and require a massive stretch of the imagination to arrive at.

As another reviewer noted, this book comes off sounding like a deliberate joke at times. From outlandish claims to having the facts wrong, most readers with any background in science will find themselves wondering how the authors can get away with this. The Constructal Law really predicts that "Biological life should evolve to make the whole Earth flow more easily"? Can we really say that "the similarity in density between animals and water helps us see the evolutionary connection between the animate and inanimate world"? I hope you know that plants didn't evolve as tools for the Earth to move water from the ground to the air. And their "pores" don't open to capture sunlight, nor do their branches grow towards areas of the driest air. I'm not sure where the authors got such ideas, but they obviously didn't consult with a biologist before penning this embarrassment.

Instead of highlighting a "unifying principle for all evolving phenomenon", this book comes off a laughable. What a ridiculously arrogant book. Not recommended.

[Will · Rating 5 out of 5]

I've been waiting a while to come across a book like this one. Reading this book brought me back to when I first read The Selfish Gene. A simple, clear exposition of a principle that has so much explanatory power. Like Dawkins, Bejan offers a new and powerful perspective. But the scope of this book is far broader than anything Dawkins (or most other authors, for that matter) could aspire to.

It is extremely bold in one sense - the authors propose a universal theory of life (and a vast definition of life to go along with it).

It is also very commonsensical in another - so many of my favourite books mesh nicely with Bejan's arguments.

The constructal law, which Bejan claims to have discovered, is (despite its somewhat awkward name) a compelling change in perspective and, more importantly, a generative mechanism for the patterns of the world around us.

I wouldn't want to spoil the excellent development of his arguments by summarizing them here.

All I can say is that this book and the ideas in it are likely to have an impact well beyond most that I've ever read.

[Kyle Justus · Rating 1 out of 5]

What a crock of shit.

It's a 250 page advertisement for the repackaging of well-known physical and mathematical relationships into an admittedly successful microscale heat transfer design principle which the author has not-s0-humbly deemed to be a "law". This is followed by the dubious application of this "law" into virtually every physical, social and biological system imaginable. If we just squint our eyes, announce that everything is a "flow design" and plot a few things that look good on a logarithmic scale, the "constructal law" is pretty much the unifying theory (sorry, "law") and can explain everything from why Michael Phelps is fast and how ejaculation works (seriously). Isaac Newton famously said "If I have seen further, it is by standing on the shoulders of giants." Instead of following the same approach, the author decided to just drape those in giants in a shirt reading "constructal law" and call it a day. This book is the scientific equivalent of trying to make "fetch" happen. Stop trying to make "fetch" happen.

[Socrate · Rating 3 out of 5]

Adrian Bejan, renumit pentru teoria constructală care explică formarea structurilor de flux în natură, ne oferă în volumul său “Libertate și evoluție. Ierarhii în natură, știință și societate” o explorare ambițioasă a interconectivității dintre formele și procesele observate în natură, știință și organizarea societăților umane. Cartea se distinge prin efortul său de a unifica domenii aparent disparate sub un principiu fundamental: nevoia de libertate pentru a permite fluxul și evoluția eficientă a tuturor sistemelor.
Bejan își începe argumentația cu ideea că evoluția nu este doar un proces biologic, ci un principiu universal aplicabil tuturor sistemelor care transportă ceva – de la sângele din venele unui organism la vehiculele pe autostrăzile unei metropole. El demonstrează cum toate aceste sisteme se supun unui principiu de bază: dorința de a evolua astfel încât să minimizeze rezistența la flux, crescând astfel eficiența. Acest principiu, pe care el îl numește "principiul constructal", devine piatra de temelie a argumentului său.
O mare parte din valoarea acestei cărți provine din maniera în care Bejan combină o vastă gamă de exemple și date științifice pentru a ilustra aplicabilitatea largă a principiului constructal. El analizează formarea râurilor, modul în care pădurile de copaci optimizează captarea luminii solare, dezvoltarea orașelor și chiar structurile organizatorice din companii și societăți. Bejan susține că ierarhiile apar în mod natural și inevitabil, oriunde există flux – fie el fizic, informațional sau social – și că acestea evoluează pentru a asigura cel mai liber și eficient flux posibil.
Cartea excelează prin claritatea cu care autorul își prezintă ideile și prin stilul său captivant, care reușește să simplifice concepte științifice complexe fără a sacrifica rigoarea. Bejan este un povestitor talentat, iar scrisul său reflectă o profundă pasiune pentru descoperirea de noi legături între fenomenele naturale și comportamentele umane. Argumentele sale sunt susținute de o abundență de date empirice, grafice și diagrame care ilustrează felul în care principiul constructal explică o gamă largă de fenomene.
Cu toate acestea, există și câteva puncte care ar putea fi criticate. În dorința sa de a oferi o teorie unificatoare, Bejan riscă uneori să supra-generalizeze. Deși teoria constructală este extrem de puternică în contextul sistemelor fizice și biologice, extinderea acesteia pentru a explica toate formele de organizare socială și ierarhiile culturale poate părea forțată. Societățile umane, deși influențate de constrângeri naturale, sunt marcate de complexități istorice, culturale și politice care nu pot fi explicate doar printr-un singur principiu fizic.
Mai mult, în capitolele în care abordează organizarea socială și politică, Bejan tinde să evite discuțiile aprofundate despre inegalitatea de putere și impactul socio-economic al acestor ierarhii. Faptul că ierarhiile sunt „naturale” nu implică neapărat că acestea sunt și echitabile sau inevitabile în toate circumstanțele. Criticii ar putea argumenta că această lipsă de nuanță lasă loc pentru interpretări potențial simpliste sau deterministe.

[Rob · Rating 1 out of 5]

Let me start my review of this book by stating up front that I am not a scientist, so you can judge what I'm going to say here accordingly. With that being said, I don't really see what Adrian Bejan's constructal law is telling us that the Maximum Power Principle (MPP) didn't already tell us nearly a hundred years ago. The MPP was first articulated by Alfred J. Lotka in the 1920s and later proposed by Howard T. Odum as a fourth law of thermodynamics. According to Odum, "The maximum power principle can be stated: During self-organization, system designs develop and prevail that maximize power intake, energy transformation, and those uses that reinforce production and efficiency." That doesn't sound terribly different from how Bejan's constructal law maximizes flow. The only thing I can see that the constructal law really brings to the table is in specifying that these developing system designs will invariably take on a tree-like, or vascular, shape. I'd like to hear Bejan explain how his constructal law integrates with, or supersedes, the MPP, but we don't know because Bejan simply ignores it. I don't know if Bejan mentions the MPP in any of his later books, but in 'Design in Nature' there is not a single mention of it.

But that's not my main objection to the book. What I find more questionable are some of the sweeping conclusions that Bejan draws from his presumptive law, and, more specifically, several other things he chooses to simply ignore. For Bejan, there seem to be no limits to what evolving flow systems can accomplish. Energy seems to exist in infinite quantities for flow systems to exploit, and there are no side effects for exploiting it. It's onward and upward with infinite growth and a never-ending march of progress – progress which is made possible by ever-improving flow systems that all march in step to the tune of the constructal law. This concentration on the flow system, rather than on what is flowing through the system, allows Bejan to ignore the big elephant in the room, which, of course, is fossil fuels. While the unstoppable march of progress that Bejan applauds is enabled by flow systems that are increasingly able to access and exploit fossil fuels, it is the fossil fuels flowing through that system that are the real drivers of that progress. Industrial civilization owes its success entirely to the concentrated power released by the burning of fossil fuels. But Bejan chooses to ignore this, along with the fact that they are a non-renewable resource, and that their burning has serious planetary consequences. Peak oil and climate change are never mentioned at all, let alone as possible limiting factors to the infinite growth the constructal law is supposedly orchestrating. Instead, Bejan would have us believe the constructal law predicts the inevitability of a capitalist paradise where accelerating energy consumption and GDP growth will continue forever. For Bejan there simply are no limits to this scenario.

These extraordinary predictions stand in stark contrast to the work of fellow-Romanian, Nicholas Georgescu-Roegen. It's interesting that Adrian Bejan and Georgescu-Roegen were both born in Romania, separated by 46 years and less than a hundred miles, and both later emigrated to the US to embark upon careers deeply involved with thermodynamics. But that's where the similarity ends, for the conclusions they draw are diametrically opposed. Unlike Bejan, Georgescu-Roegen's work with thermodynamics led him to conclude that there are indeed limits to growth. Low entropy energy is limited, it is continually being degraded into high entropy waste and pollution, and that resource depletion and ecological collapse are the inevitable consequences. Georgescu-Roegen's work gave birth to the concept of ecological economics and heavily influenced the Club of Rome's groundbreaking 1972 report, 'Limits to Growth'.

So, we have thermodynamics being used to predict an era of infinite growth and ever-increasing energy consumption on the one hand, and increasing energy scarcity and collapse on the other. Which, if either, of these two is right? Are there limits to growth, or are there not? Well, Georgescu-Roegen's work has seen its share of both praise and criticism over the years. Bejan himself, on page 149 of his book, says, "literary authors and social scientists have misused the concept of entropy (suggesting that all systems will tend toward disorder)", which, I suspect, is a swipe aimed directly at Georgescu-Roegen. Despite this, if we look around the world, Georgescu-Roegen seems to be in closer alignment with the observable evidence. Climate change is unfolding all around us with increasing severity. The energy return on investment (EROI) of fossil fuels is continually falling, with energy thus becoming more expensive. It would take the equivalent of 1.7 Earths to satisfy our current consumption habits, which is obviously unsustainable. Choosing to ignore these things, as Bejan does, doesn't make them go away. It appears there are indeed hard limits to growth that the constructal law is incapable of circumventing, regardless of how well flow access is maximized. Bejan blithely assures us that his law will prod us to both innovate our way around these obstacles and find alternative fuels, but these assurances seem to involve more wishful thinking than actual physics.

Bejan derides the 19th century social Darwinists for misapplying evolutionary science in an attempt to justify their own social and political advantages. Unfortunately, once Bejan has laid all his cards on the table in the concluding chapter, we see that he is doing the exact same thing himself. He attributes the trajectory of social evolution to the workings of the constructal law, while assuring us, in true Panglossian fashion, that political hierarchy, economic inequality, and ecological ruin from of a global capitalist system bent on the pursuit of infinite growth, really is the best of all possible worlds. Sure, we can tinker with all these things in a limited way, but physics allegedly tells us they all exist, and will continue to exist, because the constructal law decrees they must. Those, like Georgescu-Roegen, who maintain that there are limits to growth are simply on the wrong side of physics. While there may indeed be a constructal law (or a maximum power principle) that is pushing us in the direction of ever-increasing energy consumption, it is a path that is wholly unsustainable. Bejan may be able to ignore resource depletion and climate change, but the constructal law cannot. If we don't find a way to limit our growth and consume fewer resources, the whole system is going to come crashing down around us, just as Georgescu-Roegen predicted. In the end, I suspect those predictions will prove to be far more accurate than the ones Bejan makes through the over-use of his constructal law.

[Thomas · Rating 3 out of 5]

The hypothesis of this book is that an innate goal of nature is to accomplish its flows of energy and matter with the least dissipation of energy in the form of useless heat; and that the evolution of things toward this goal leads to the profusion of complexity found in nature, including to living things.

The author proclaims this and illustrates it with numerous examples to provide evidence. He does this in an arrogant and self-promoting way that many others have noted in their reviews. Let me just add that it seems the height of arrogance to appeal to physics as the author does, while failing to ever mention that physics has embraced a "principle of least action" long before the author came on the scene. There is plenty of literature on this subject even though the author writes as if he invented the idea. There is even a chapter on this in the Feynman Lectures, entitled "The Principle of Least Action". [Feynman et al., Lectures on Physics, VII, p.19-1 to 14].

As intriguing as the consequences of this principle as identified in the book may be, it is unconscionable to promote oneself as the originator of an idea that has a long history in physics, without ever pointing this out or showing how one's own contribution is distinguished from prior work. It's a shame that a better job could not have been done of that, because it will cause an interesting book to be discounted by many readers.

[Grace · Rating 3 out of 5]

Solid first few chapters, gradually became just a bit too much for me. Too much repetition. I actually just skimmed the last few chapters instead of fully reading them, which I almost NEVER do, just to be done with it. Good resource tho and shoutout to the authors for being referenced in one of my reference papers on biophilia and child development last week. Good going, lads!

[Clark Hays · Rating 4 out of 5]

Everything is channels and flow

After reading Design in Nature, by Brian Bejan, everything seemed to change just a little. I imagine this is what it might have felt like after reading Darwin before evolution was an accepted theory. Bejan writes about another natural force he calls the constructal law. New to me, the concept is that anything that flows — and practically everything flows — is governed by an organizing principle that maximizes the efficiency of flow against resistance. The thought that there is a force as fundamental as gravity that seeks perfection and shapes everything around is at once liberating and a little disorienting. It feels like an unified theory of everything, only in the very early stages.

According to the author, we are governed by constructal law, both a product (our bodies and the way we move are functions of flow) and master of it — we unconsciously and consciously organize our roads and cities by the design elements, our engines and flying machines are an extension of constructal law and even our language and printed words evolve in accordance with maximizing flow. It is unavoidable, inescapable, predictable and continually evolving itself toward greater perfection (in this case, perfection means the most efficient transfer of flow in relation to force expended against resistance; it’s not subjective perfection).

Whatever flows moves through channels that necessarily take the form of tree-shaped structures – main arteries branching off into smaller ones until whatever is flowing arrives at its destination effectively and efficiently. The tree-shaped structures can be physical, as in river basins, human capillary systems for moving blood, snowflakes or crystals, or they can be conceptual such as the flow of information, the distribution of top-ranked colleges or the speed of competitive swimmers.

This was not an easy read for me — the peppering of arcane equations throughout made my eyes glaze over at times — but it is well worth the time and I recommend it. But be warned, he writes with an irritating sense of authority that, while probably deserved, stifles tangential thinking. A I found the details from his personal life distracting, they weren’t detailed enough to illuminate the science and so seemed to clutter up the hard edges.

There is much to this area of thought and I look forward to reading the next generation books that emerge from constructal law theory, and hopefully they will be written by ethicists. As Bejan is quick to point out, constructal law makes no value judgments and I could see, if left untended, constructal law used to justify preserving the status quo in systems that prevent equity. For example, he discusses the effectiveness of hierarchy in corporate settings as the most effective way for responsibility to flow. I would hate to see the distribution of wealth somehow tied to constructal law and those on the far ends of the branches left to fend for themselves, far, far removed from the main channel.

Here’s a great line (from page 147): “The constructal law places a physics principle behind Darwin’s idea about evolution. It tells us why certain changes are better than others and shows that those changes do not arise by accident but through the generation of design.”

[Dan · Rating 4 out of 5]

The premise of the book is that nature (which include all of us) follows a basic law of construction and how energy is dispersed over a system. If you look at a tree and the way the branches grow out from the trunk, this is the same structure as a river system, the human lung, lightning and social organizations (larger branches dispersing energy and work into smaller and smaller branches to effectively move energy and produce work efficiently). Following the laws of thermodynamics, energy gets dispersed and nature constructs the same system and path for all organisms. Based on construction law, scientists can predict systems and structure. This applied to athletics where they were able to predict and map out the paths of runners and swimmers knowing how energy is dispersed over a system. I enjoyed reading this book. A little too technical at times. The book outlines that basic premise that nature follows basic laws to move energy efficiently over a period of time and given system to more effectively produce work. Or, to state the opposite. Nature is not random but there is a logical, unified system that governs growth and work.

[Patrick Gendron · Rating 5 out of 5]

An essential book for anyone who wants to realize or speculate about the future of their work, society, and the world. I thank Adian Bejan for broadening my realization of multiple concepts, including evolution, life, and systems. A must read.

[Lori · Rating 2 out of 5]

A potentially valuable insight and tool buried in hubris and poor writing. The basic idea is to apply the basic laws of thermodynamics to living organisms (and social structures and human knowledge/science). Instead of looking at static structures we need to look at how energy/mass flows through them.

A good seminar could be made by critically detailing Bejan's misconceptions and errors.
1) He really doesn't understand Darwin or Steven Jay Gould.
2) The whole scaling concept was known and used 30 years ago when I was a graduate student studying evolution. However what we were interested in were the deviances from the norm, not the line. Bejan calls this getting lost in the details.
3) I see no convincing proof that knowledge/information follows the laws of thermodynamics. As far as I can tell, knowledge doesn't care who or whether it is known.

See Michial's review.

[Chris Kargel · Rating 4 out of 5]

I became both enamored and annoyed by this little treatise. The idea of searching for a unifying force behind the driving life of both animate and inanimate objects sounds so appealing, I couldn't help but almost cheer at the celebration of Movement. However, I would have easily wanted to avoid the grandstanding and self-indulgence the author offered. When he started talking about how all the ideas of early thinkers coalesced into the law of gravity, I shuddered at the obvious direction of his thought: that all the ideas of all of science coalesce into his tidy law. This whole thing could have been done, and done beautifully, without having the author declare himself the heir of all scientific thought. Oh well, it still offers some grand and wonderful ideas, if I can just ignore the ingratiation probably brought about by a life in academia.

[Nick Gogerty · Rating 5 out of 5]

Very well done and simple exposition on constructal theory. the insight of scalar laws leading to change in all systems are important. the basic premise of increased flow leading to phase shifts and bifurcations are very beuatiful discoveries in science and complex systems including social and economic ones. this is a very accessible and fun science book.

[Ashwin · Rating 3 out of 5]

Interesting premise and well presented. At some point though it seems that they are trying to stretch a simple idea too much to fill the pages.

[Alexandra S · Rating 5 out of 5]

It is so illuminating that I want to keep it a secret

[TJ Ryu · Rating 5 out of 5]

Bridge

The writer can make a bridge between the animated and inanimated. The constructal law made me think about many things about evolution.

[Abner Rosenweig · Rating 3 out of 5]

Constructal Law is revolutionary and broadly applicable in the diverse areas of science, technology, and even society. It resolves the question of why trees and arteries and lightning and riverbeds all have similar fractalesque patterns, for example. And after Bejan's introduction of the constructal law, Jeremy England came forth with his dissipation-driven adaptation hypothesis, which startled the physics world with an explanation of how the laws of thermodynamics might predispose life to emerge in the universe. While England got a great deal of academia limelight and Bejan has remained in the shadows, few recognize England's hypothesis is just another application of constructal law.

While the notion of constructal law is groundbreaking, the book itself feels long-winded and repetitive, and Bejan and his writing sidekick Zane occasionally push too far, making some of their claims laughably grandiose.

The book does a serviceable job identifying the "flow system" and demonstrating how many operations in nature and culture adhere to the constructal dynamic: "For a finite-size flow system to persist in time, its configuration must evolve in such a way that provides easier access to the currents that flow through it," Bejan observes.

It is also inspiring to realize that earth's complex features often don't exist as isolated phenomena but as part of a larger system in the global flow. For example, trees are cited as a pumping station for ground-to-air water flow. This makes me wonder how other common structures serve in the flow system at different levels: human body, society, the earth, and beyond. Does the constructal law imply that the universe itself maximizes flow? If so, how?

The implications of constructal law for science, tech, and social institutions, economics, politics, urban planning, and ethics are immense. The idea could stimulate thousands of master's theses and our entire global civilization could, probably should, be designed with principles derived from the law.

But the book goes too far. Bejan wants to redefine life as everything that moves and morphs in order to flow. I'm not sure why this redefinition is necessary. Isn't it enough to observe that nature operates in a nested, interconnected series of flow systems?

Things really go into the woods when Bejan attempts to apply his natural law to society and culture. Bejan claims social systems naturally, inexorably follow the constructal law, moving toward the highest good. It's absurd to believe human society unconsciously obeys this law when those in power deliberately undermine the common good to satisfy their greed. In the past, this greed has led to the collapse of empires and history will undoubtedly repeat itself. Society doesn't naturally conform to any grand evolutionary purpose that will lead us to a promised land, and it's deeply out of touch and insulting to the fallen societies and spoiled habitats on the planet to suggest that everything always works out for the best.

In his assessment of society, Bejan oversimplifies. Perhaps our economy has maximized the flow of goods over time, but Bejan neglects to factor in the flow of money--the distribution of income in our hypercapitalist economy is wildly out of control and far beyond the constraints of any regulatory law of nature. "On the world stage, you can place solid bets that the entire globe will continue spreading the rule of law, free trade, human rights, globalization, and all the other design features that guarantee more movement for us and our stuff... because of physics" (258). What a relief! I was concerned our global economy and social institutions were off track, but we have nothing to worry about because physics. Thank you, Professor Bejan! Haha.

Constructal law is an incredible idea. Properly understood, it would revolutionize civilization. That said, I'd also encourage the author to know the law's limits and to be cautious of excessive claims.

[Christopher · Rating 3 out of 5]

This was a hard one to rate, since I couldn't give it a 2.5. I decided to round up because I thought it offered some useful examples and the general gist of it was worth engaging with. To explain why I will split up the positives and negatives below:

Positives:

-We need more people undermining the absolute distinction between biological life and non-life chemistry. Speculative realist philosophy often does this on the humanities side, so its great to see people with engineering/science backgrounds doing it on the other side.

-Constructive flow theory is incredibly useful. Its not as well put as a theory of everything being the moving of stuff around as the physics book 'Shell Beach' by Jesper Moller Grimstrup does, but its intriguing and offers some great examples of how flow maximizes efficiency.

-Constructal Law clearly could be explored more to help flesh out more philosophical ideas, and so, even if you hate this book, its probably worth engaging with on some level.

Negatives:

-He may not have had the science to back up his claims, but Lao Tzu beat Adrian Bejan to the punch by a few thousand years here, and yet nowhere is even a mention of him in this text.

-Some of the examples are not as definitive as the author thinks they are. His favorite flow systems to reference are river beds and forests. When he goes into the flow system being 'progressive' (i.e. always getting more efficient with time) he forgets that he is isolating his examples rather than leaving them as part of a dynamic world where other flow systems clash with them. Forests and river beds may behave a certain way constantly *if left alone*, but climate changes, plate tectonics grind on, forest fires arise. The system may have tendencies to constant flow improvement, but it also dramatically resets due to unexpected events. Sometimes, this allows another process to take over space from the old one. Points in camp Taleb and Darwin and not for Bejan here.

-See point above, now imagine what the author's politics are. Yeah. This is the worst part. Some very Stephen Pinker-y leaks seep in, undermining the text. Lukewarm NYT op-ed page tier takes on politics and a neo-Victorian/Whiggish view of history come across as a desperate attempt to salvage faith in the traditional liberal project. But much like riverbeds or life on earth, all things live in borrowed time. 'Civilization', after all, actually decreased the quality of life for most people adopting the agrarian lifestyle of a very long time before it started to deliver truly positive benefits across the board. It is also currently cooking up the biggest environmental crisis in recorded history. Plenty of ideological doctrines, which the author also awkwardly tries to put into his framework, have also had debatable and even net negative impacts on human culture. Periods of divergence can be a boon for human innovation, and unity and merging can sow the seeds of decline through the complacency they engender. This is why there is no 'arc of history bending towards freedom' or 'right side of history.' The author blithely stating we live in greater freedom now, in a time when anyone can be fired for saying the wrong thing on their own time and state surveillance capacities are beyond anything ever seen before is simply laughable.

Bejan should stick to hard science. It would serve his core arguments about the physical world much better.

[Sully · Rating 3 out of 5]

The constructal law is cool, and it genuinely changes the way you see the world. Essentially, Bejan has united all objects and systems in the world by defining, if broadly, what it means for a design to be ‘better.’ There are some truly revelatory passages in here… and the fact that he could do all that, and still make me loathe him is impressive.

Bejan lacks any humility whatsoever, triumphantly proclaiming he has created a new epoch of science… this book was written 10 years ago, and no such era has arisen. That would be acceptable, but, at the end of every chapter—after Bejan has said something cool and interesting about animal motion or trees—he tries to broaden the point, making sweeping statements about life, design, and the universe. These passages are utterly impenetrable, but kinda fun to read.

The real issue is that he then mobilizes his scientific theory to make statements about society, politics, and economics. Some of these statements do seem to be in line with the constructal law, but others use shoddy or half-assed reasoning to essentially confirm his priors. In particular, he states that the constructal law proves that free society, free trade, and other aspects of neoliberalism are scientifically correct prescriptions for humanity. At times, he makes outright problematic statements about how people are “choosing to put on suits and speak English” or that North America and Europe are hubs of humanity. Because the constructal law suggests that hierarchy is a good design, Bejan seems to think that existing hierarchies are good as they are now. His idea of change is also confusing. He believes that change is critical to good design, to evolving design, but then points to traditionally liberal kinds of change, such as high-speed rail on the East Coast or political correctness on college campuses, as bad design.

And, more broadly, the superimposing of this natural law of design on human behavior all but negates important things, like… human agency, morality, and ethics. Perhaps Bejan’s most neoliberal idea of all is that efficiency is a suitable stand-in for morality. His thesis seems to be not that “the moral arc of the universe is long, but it bends toward justice,” but rather that it bends toward efficiency.

So, it’s an interesting book, I’m glad I read it, especially as an engineer. But, given Bejan’s utter lack of self reflection and humility, you can only take it so seriously.

[Sean · Rating 5 out of 5]

I finished reading Design in Nature: How the Constructal Law Governs Evolution in Biology, Physics, Technology and Social Organization by Adrian Bejan and J. Peder Zane. This is a brilliant book, probably one of the most important books on the social and political aspects of thermodynamics written in the past ten years but for two very different reasons. One: the author brilliantly describes an implicit law or potential first principle of nature, the Constructal Law, which describes how the tendency for an increasing and more efficient movement of mass and energy through time is ruled by a physical law. This, the book asserts, naturally creates many complex designs that we see in nature. The second reason, which is not quite so flattering, is that his book clearly describes the approach of the modern mind—that despite all his arguing to the contrary, points in the direction that consciousness is either a feature of matter and energy or “the designer” cannot be conceived properly using the imagery of Bejan’s schoolboy God. Bejan absolutely fails to describe what should be obvious to all but not to those who refuse to look: that the universe is, from the point of view of common sense, not unintelligently self-assembling and that the postulated Fifth Law, negentropy, which assumes some sort of teleology in the universe, really needs to be looked at more closely for a more accurate and scientific accounting of the universe. More on negentropy in a moment.

Let’s look closely at what Bejan says:

“Of course, there is no conscious intelligence behind these patterns, no Divine Architect churning out brilliant blueprints. To pre-empt any confusion, let me make this perfectly clear: The constructal law is not headed toward a creationist argument, and in no way does it support the claims of those who promulgate the fantasy of intelligent design…[How can he possibly know this from a scientific perspective? Better to take a more agnostic and humble position as in: “we don’t know-period”]. Bejan goes on to say: this raises the question: How come? What causes the constructal law? The short answer: we don’t know. The constructal law is what is known in science as a first principle, an idea that cannot be deduced or derived from other laws (if it could, it would be a theorem. It just is—a law of physics that governs the emergence of macroscopic shape and structure in nature. The constructal law tells us why those patterns arise and empowers us to predict how they should change in the future. It reveals that it is not love or money that makes the world go round but flow and design.”

This is quite amusing from a metaphysical perspective. He knows that intelligent design is a “fantasy” but he doesn’t know why the constructal law works. Just make up first principles and poof—no need to inquire further. This sort of argument, much like natural selection being pimped as the only motor of evolution, is a partial explanation posing as a final theory. Entropy does create efficient dispersion patterns from an original energy source, and while it very well describes vice, moral virtue and the human tendency to invest enormous energy into belief and other systems might be thought of as being somewhat alien to the constructal law and much more closely related to negentropy or the tendency to wind things up. Note how negative entropy is described in the dictionary: “Negative entropy, or negentropy, roughly refers to the degree of order or organization within a closed system.” That is only part of what negentropy might mean. Here is the alternative scientific description noted in God Has Skin in the Game:

“There are, technically speaking, only Four Laws of Thermodynamics but a Fifth Law of Thermodynamics has been proposed by physicist Philip Carr:

“The missing link in thermodynamics as taught in schools today seems to be a concise explanation of why order and structures abound in a universe purported to be driven by a Second Law [popularly known as the Law of Entropy] that states that disorder increases, always and everywhere. This short note is provided in order to stimulate discussion around a possible Fifth Law which predicts what we observe, which is that order and structures should actually predominate in the world in which we live.” Based on this model and observations the proposed 5th Law of Thermodynamics criticizes the notion of stochastically generated order.

"An open system containing a large mixture of similar automatons, placed in contact with a non-equilibrated environment, has a finite probability of supporting the spontaneous generation and growth of self-constructing machines of unlimited complexity." This proposed Fifth Law of Thermodynamics is also known, in some circles, as negentropy. Negentropy was proposed by the physicist Schrödinger as a kind of free energy that accumulates within systems that store energy but it is facetious to assume that the storage of extra energy might necessarily result in greater order, (and complexity) except by way of increasing the means of storage. The Fifth Law of Thermodynamics supports the notion of creation by an outside force such as the Unmoved Mover or God. “

So, let’s get back to my favorite subject, Existence. Existence does NOT exist—it IS. Something that does not exist generates all that exists. Energy and mass exist, therefore, there are only two possible conclusions regarding origin. One: energy is eternal and concomitantly, consciousness may only be a higher order feature of energy and mass. This is the position of an elevated atheism. Two: all that exists depends on something that does not exist. This is the philosophical and metaphysical explanation of Aristotle and St. Thomas Aquinas that leaves the door open to providence, grace, honor and beauty. The former is a closed universe going nowhere. When you die you return to energy for re-cycling. End of story. The world of negentropy preserves a universe where honor, beauty and goodness are desirable for more than just subjective reasons. Where is the goodness and beauty in the cold atheism of abortion or the moral weirdness of homosexuality? The desire for a stochastic or randomly generated universe is a moral-free universe from the perspective of objective morality. A stochastic universe fits the process morality of pure subjectivity and is the universal choice of moralists on the left. Make no mistake about it. The present political tension in the US is really about atheistic morality versus the flawed but traditional morality of the Founders. Conservatives, for all their faults, tend to support the intent of the Founders. What the left thinks it is supporting in nothing but entropy in the guise of concern.

Throw a set of marbles down and watch them roll. They will describe a random pattern of energy dispersion based on various resistances of friction, gravity, direction, etc. What the pattern does not tell you is who threw the marbles.

[Peter Aronson · Rating 3 out of 5]

Sometimes, someone has or learns an idea that explains a bunch of what previously have been thought to be unrelated phenomena. This is very exciting, and if they are not careful they will start to claim to see applications of their idea everywhere. If they are intellectually honest, they will at some point pull back and reduce their claims (Benoît Mandelbrot might have claimed to have invented "the science of earth forms" in Fractals: Form, chance, and dimension, despite the field of geomorphology being over 100 years old at the time, but by The Fractal Geometry of Nature he had dropped that claim). If not, they then see proof of their idea everywhere, and disproof of it nowhere. That's where Bejan and the "constructal law" seems to have ended up. Which is unfortunate, as there are some interesting observations here, even if marred by overreaching, teleological thinking, "just so" stories and imprecision.

(There seems to be a phenomenon where at some point in the career of successful, intelligent man (it may happen to women too, but I've only observed it so far in men) where their ego metastasizes and they think they understand all fields of study: see Biocentrism: How Life and Consciousness Are the Keys to Understanding the True Nature of the Universe and A New Kind of Science.)

Do I recommend you read this book? Maybe? He talks about flows getting "better" over time, but doesn't define better until page 41, and then it's a rather vague definition to cover so many different things. There is a lot of interesting stuff in here, but Bejan almost never shows his work – it's almost always how he (and usually someone else) go off, and using simple geometry and arithmetic discover this amazing correspondence (except these are, at least in this book, always ex post facto "discoveries" that merely confirm what was already known). Not to mention all the insights he vouchsafes us that other have had long before (or the simplistic views he attributes to scientists who commit the sin of disagreeing with him). And then there are the last two chapters where he really lets his enthusiasm run away from him, where he wields his beloved hammer of his constructal law against every nail in sight, and everything looks like a nail to him...

[Paul · Rating 4 out of 5]

Another science book I decided to read! Good brain exercise but not an exciting one in my opinion as it took a lot of concentration to get to the end (my issue, not the author's). Certainly would have been better if I was also sitting in the author's classes to get a better understanding of his concepts and thus had the opportunity to ask a few questions. I struggle with his idea of a constructal law vs gravity defining much of these "flows" but he's more knowledgeable than I on these issues and how they connect. Did find some interesting excerpts below worth additional thought on my part....

- Everything that moves, whether animate or inanimate, is a flow system. All flow systems generate shape and structure in time in order to facilitate this movement across a landscape filled with resistance (for example, friction).
- This treelike pattern emerges throughout nature because it is an effective design for facilitating point-to-area and area-to-point flows. Indeed, wherever you find such flows, you find a treelike structure.
- ... the physics concept of the dead state, which means "equilibrium with the environment" in thermodynamics: a system that is at the same pressure, the same temperature, and so forth as its surroundings, and hence, in which nothing moves.
- The design of our bodies... has evolved to enable us to cover greater distances per unit of useful energy (food, fuel).
- When lava pours out of the volcano, another remarkable phenomenon occurs: the lava seems to select between two flow options, choosing the better way to move at any given time.
- If it is moving quickly, it generates a different flow configuration - a treelike structure with channels and branches - because this is the better way to move quickly.

[Aidan Wyber · Rating 4 out of 5]

It seems to me that Bejan offers only a law and not an explanation of design in nature as he claims. Nevertheless, it does seem to hold in its 'predictive' capacity, but he has tried to approach phenomena naively as if they never existed, but doesn't mention any possible biases, prejudices.

The language of the book is arduous, dry and very repetitive. There are unnecessay speckles of claims to atheism. Watch out for his generalisations into the moral domain, but do contemplate them. There is also a fair bit of self-referencing to watch out for.

I still believe the core of the law is extremely potent. As an industrial design student, it has radically transformed how I see design and life, in my own life. I would sorely recommend it to anyone who is generally interested. You can probably understand it after reading the first and last quarter of it.

For further reading, I'd highly recommend the work of Jeremy England and his research group on the thermodynamics of life-like systems. I'm far from expert, but it seems to me there is a strong convergence in the idea that systems that dissipate more heat are more likely to survive.

[Samuel · Rating 2 out of 5]

This book was one of the most aggravating I've read in a long while. It has an interesting central concept, but one that is overstated in its importance and reductive of the very systems it is supposed to describe to say the least. The writing is poorly organized, and appears to be aimed at readers who aren't scientifically-focused, but undermines this with poorly-explained examples including technical phrasing, terminology, figures, and equations, so it's unclear who the authors are addressing. It is clear that the authors believe that they have a much stronger grasp of a wide range of fields that they aren't competent in, including biology, history, and sociology. Throughout, concepts are poorly defined (and incorrectly at that for the ones with definitions) in order to vaguely apply the "constructual law" to their examples. This "constructural law" is, as stated above, an interesting idea and may be a useful tool for understanding certain natural or unnatural designs, but it utterly fails as the natural law the author claim it is. I can't say this book was a complete waste of time, but it was a significant disappointment.

[Al Parker · Rating 1 out of 5]

I don't usually write bad reviews for books. If it is a three or less I don't rate or review it.
I leave that task to others as I don't enjoy pummeling fellow authors.
I make an exception with this book. The silly ideas on entropy combined with the sense of self-importance this author regards himself demand being called out.
As other reviewers have noted, the author feels he has discovered a law of nature. That is quite a claim and is best left for your peers to determine (which they don't seem to be lining up to do).
Too bad because there are a few concepts that are interesting and might be worth investigating., but the author has shot his credibility.
Don't bother with this one.