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The Case Against Reality: Why Evolution Hid the Truth from Our Eyes

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Can we trust our senses to tell us the truth? Challenging leading scientific theories that claim that our senses report back objective reality, cognitive scientist Donald Hoffman argues that while we should take our perceptions seriously, we should not take them literally. How can it be possible that the world we see is not objective reality? And how can our senses be useful if they are not communicating the truth? Hoffman grapples with these questions and more over the course of this eye-opening work. Ever since Homo sapiens has walked the earth, natural selection has favored perception that hides the truth and guides us toward useful action, shaping our senses to keep us alive and reproducing. We observe a speeding car and do not walk in front of it; we see mold growing on bread and do not eat it. These impressions, though, are not objective reality. Just like a file icon on a desktop screen is a useful symbol rather than a genuine representation of what a computer file looks like, the objects we see every day are merely icons, allowing us to navigate the world safely and with ease. The real-world implications for this discovery are huge. From examining why fashion designers create clothes that give the illusion of a more “attractive” body shape to studying how companies use color to elicit specific emotions in consumers, and even dismantling the very notion that spacetime is objective reality, The Case Against Reality dares us to question everything we thought we knew about the world we see. 40 illustrations; 8 pages of color illustrations

272 pages, Hardcover

Published August 13, 2019

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About the author

Donald D. Hoffman

10 books330 followers
Donald D. Hoffman received a Ph.D. from MIT in 1983 and is a Professor of Cognitive Sciences at the University of California, Irvine. His research on perception, evolution, and consciousness received the Troland Award of the US National Academy of Sciences, the Distinguished Scientific Award for Early Career Contribution of the American Psychological Association, the Rustum Roy Award of the Chopra Foundation, and is the subject of his TED Talk, titled "Do we see reality as it is?"

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Profile Image for BlackOxford.
1,095 reviews69k followers
March 6, 2023
You Can’t Get There From Here

Reality has no intrinsic properties. Reality exists but existence is not a property. Hoffman’s thesis is that human beings, in fact all life, have evolved such that they impose properties on reality that are relevant to their survival as individuals and as a species. We do not simply notice certain properties about reality - length, colour, texture, taste smell, certain frequencies of vibration, etc. - we are literally the source of these properties. They would not be there unless they were noticed by us.

I know, I know. This is a bit like finding out in old age that the woman who brought you up is not your mother. The realisation that the creation stories in the book of Genesis are essentially true might come as another shock.* Evolution has separated the sea from the land, allowed us to see a spectrum of light, and populated the world around us with useful, beautiful, as well as less useful and decidedly dangerous things. And we have given these things names as we perceive them.

Confronted with the proposition that everything about the world except its being is actually in our heads, has, I’m sure a similar impact to Darwin’s announcement that apes are our cousins and that our joint ancestors climbed out of the ooze together. The proposition initially appears incomprehensible.** Surely this is some sort of deconstructionist ploy by some wily Frenchmen to undermine both confidence in our own judgement and the foundations of civilised society. I know what the objective properties of a tomato are as I hold it in my hand. Truth doesn’t depend upon perception; it’s the way things really are.

This is a difficult belief to overcome. The redness and lovely sweet/sharp taste of a tomato are facts that can’t be doubted. To paraphrase Dr. Johnson, I refute any claim to the contrary by simply eating it.*** But think about how a tomato appears and tastes to a bat, or a fungus, or a fruit fly. The first, uninterested in the tomato entirely, may only clock the entire tomato plant as a single entity without colour or taste. The fungus may not even notice the tomato until it has fallen from the vine and become desiccated. All the fruit fly senses is a cloud of sweetness from neuronal activity that we can only imagine; the tomato may be indistinguishable to it from a potato, or a garbage dump.

The obvious point is that the reality is perceived depends on the sensory apparatus at hand. The senses developed through evolutionary adaptation therefore determine what is seen, felt, heard, tasted, feared, and desired. The perceptions of human beings may be differentialy unique but they are not superior to those of the bat, fungus or fruit fly. They are a sensory interpretation of reality which have proven useful for each species. But they are not reality. They are not even aspects of reality. They are ‘merely’ chemical, visual, and nuclear interactions with reality (the last being particularly important for the bacteria which ‘eat’ radioactive material).

The reason that this is difficult to accept, as difficult to accept perhaps as the Church’s difficulty in accepting Galileo’s assertion that the earth revolves around the sun when it obviously doesn’t, is the same reason that we can discuss the difficulty at all: language. Even if bats, fungi, and fruit flies had a language, it would be incomprehensible to human beings because we cannot perceive the world as they do. So we could care less about their language, including their concepts, categories of thought, and intra-species arguments about the way the world really is.

But we are entirely immersed in human language. We are quite literally in each other’s heads through language. The words, syntax, concepts, and literal connections we make among them ‘live’ simultaneously in billions of people. Just like the bacteria that live in our guts, we depend upon this linguistic virus for our existence. Yet as Hoffman points out, language promotes our success as a species, it does not reveal reality. Hoffman uses the apt metaphor of computer desktop ikons to make the point:
“You may want truth, but you don’t need truth. Perceiving truth would drive our species extinct. You need simple icons that show you how to act to stay alive. Perception is not a window on objective reality. It is an interface that hides objective reality behind a veil of helpful icons.”


In fact language protects us from reality and allows us to function with complex, cooperative social skills. Language forces us together in order to help us survive in a unique way. We usually call this benignly invasive presence ‘culture,’ but what it consists of in practical terms is words which we use to form concepts, explanations, and theories of what reality is and how it works. We share these casually with our children, our friends and with people we have never met because they cost almost nothing to produce and create power in proportion to their dissemination.

The problem, of course, is that we tend to take these words as reality. Or as we euphemistically say, as ‘representing reality.’ However, representation is not the function of the words we use; they don’t ‘stand for’ discrete bits of reality, just as the bat’s sonic radar image, the fungus’s appreciation of radioactivity as food, or the fruit fly’s perception of an intoxicating haze. These are all purely imaginary constructions (or if one prefers: interpretations of what is there) which result from the interaction of the organism and its environment. None of these interpretations is ‘true’ or ‘correct’ except in the pragmatic sense that it fosters the well-being of the organism. In this sense it ‘fits’ with the environmental reality. But these interpretations are not approximations, or even partial descriptions, of the ‘essence,’ the ‘substance,’ or the ‘structure’ of the object(s) involved. They gave nothing to do with reality.

This is the case with systematic scientific measurement as well as with casual everyday perception. And it applies to the most fundamental concepts like space and time. Immanuel Kant, it turns out, was correct: these are categories of our minds not characteristics of the cosmos. Einstein’s theories suggests how arbitrary, how dysfunctional they are in other circumstances than planning a road trip from A to B. Quantum experiments similarly show that our distinctions ‘wave’ and ‘particle’ simply cannot be applied coherently about light. ‘Space-time’ and ‘particle-waves’ are merely garish designations that have no more accuracy about what exists than our more conventional terms. Obviously we can do more with them, that is we can combine them with other words to suggest possible implications (scientists call them hypotheses) which can then be ‘tested’ against still other words (called measurements) to judge whether all the new words fit more coherently together than the old words, and under what circumstances.

That is, in all of science as well as in everyday life, our intellectual hands never leave our linguistic sleeves. Whatever magic that is apparently produced by modern science and technological development is all ‘done with mirrors.’ We tweak reality to see how it responds in light of new concepts and theories; but we never get inside its linguistic skin. This is not a methodological defect but a benign gift supplied by the decisively complete separation of our language-abilities from our existential engagement with the world. Without this isolation of language from reality, we would be unable to think creatively, work cooperatively, or develop our survival skills from generation to generation. Language ability, our facility to keep reality at bay, is our most important evolutionary adaptation.

* As is the biblical account of the creation of light before the creation of the sun. According to cosmologists, the primordial union of electrons and protons during the first few nanoseconds of existence produced the first photons, most of which are still travelling about timelessly as the so-called microwave background radiation.

**it is relevant here to point out that it has been theology which has kept the idea of existence as not-a-property-of-things-which-exist alive through the centuries. That is, existence is not an attribute - something re-discovered in 20th Century philosophy. This may be difficult to grasp since our usual language leads us into the mistake of expressing existence as somehow ‘belonging’ to an object. In theology, for example, to say ‘God exists’ actually says nothing about the character of divinity. It is semantically equivalent to the expression ‘Reality exists.’ God is therefore often called Ultimate Reality. That is, existence as a property of neither God nor of Reality is what allows us to talk about both without immediate contradiction.

***This is the so-called argument ad lapidem named in honour of the good doctor who refuted Bishop Berkeley’s thesis about the immateriality of the world by kicking a stone. Although I have encountered it from time to time among GR correspondents, it is nonetheless a fallacy. In any case, my point here is not about the materiality of the world, whatever that is, but about its properties, or rather the properties we assign to it.
Profile Image for Infinite Jen.
93 reviews629 followers
October 13, 2022
My reaction to this book was far too uncharitable. As with any theory which seeks to dethrone a reigning paradigm, (and what could be more upsetting than a new paradigm which seeks to render all other paradigms hopelessly quaint and parochial), it is always met with resistance from those most entrenched in previous methodological frameworks. Consider the hostility with which Albert Einstein approached the findings of Quantum Mechanics. He spent much of his later life attempting to introduce hidden variables into equations in order to make them consistent with no-spooky-action-at-a-distance. We now know that this was a mug's game. Now there are some important distinctions to be made here, and the comparison between what's being proposed by Hoffman and his collaborators, and the findings of Einstein's contemporaries, share, (in my mind), two important differences which I will state in the conclusion of this addendum to my initial review. But I found it instructive to reflect on the history of scientific progress and how we can often be obstinate to our own detriment.

Anywho, here I am, after many months of flagellating myself with a sturdy rope of black liquorice while reciting these lines: "For every complex problem there is an answer that is clear, simple and wrong.” Until blood loss induced a beatific vision in which The Logos spoke to me. "Max Planck, surveying his own career in his Scientific Autobiography, sadly remarked that “a new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it.” To which I replied, "You're not The Logos! That's a passage from the work of Thomas Kuhn! I didn't just roll in on a load of turnips!" Causing the amorphous being to vanish and take with it the possibility of further interrogation.

I'm coming around to the idea that it seems very unlikely that evolution would've primed our perceptual systems to be perfectly vertical. That we would have access to things that are "true-enough" to maximize our chances of survival and reproduction - cobbling together a reasonably good facsimile within those narrow contexts - sure. But that we have access to reality, unencumbered by the limitations of our atavistic trajectories through evolutionary space? Probably not. We know that much of what constitutes the fundamental properties of the universe, (as we currently understand them), are completely unintuitive, and this is readily apparent when we move to scales and speeds at which our evolved, Folk-Newtonian physics break down completely. In the case of both General Relativity and Quantum Mechanics. To say nothing of things such as holographic theory, which suggests that our 3d reality may actually be a holographic projection of a 2 dimensional reality on the boundary of spacetime, or others which suggest extra spatial dimensions that we can't perceive. Or theories that visualize space-time as a superfluid having zero viscosity, and others which compel us to consider the possibility that we are all highly advanced sex robots seeded by an now extinct martian civilization.

And finally, the work of people like Nima Arkani-Hamed and Ed Witten who are uncovering things which lead them to suspect that maybe things we took as fundamental in physics, such a Hilbert Spaces, aren't at all. Amplituhedron theory challenges the notion that spacetime locality and unitarity are necessary components of a model of particle interactions. The connection between the amplituhedron and scattering amplitudes is a conjecture that has passed many non-trivial checks, including an understanding of how locality and unitarity arise as consequences of positivity. And I'm an Oscar Meyer Wiener. etc.

To what extent is our reality an adaptive fiction, then? I have no idea, and I'm not convinced by some of Hoffman's bolder claims - that our perception of reality isn't even an abstraction of it, but completely detached from it in a way that appears unbridgeable, for instance - but the ways in which this is certainly true provide fertile ground for study. The technical question that Hoffman and his team are grappling with is this: What is the probability that natural selection would shape our sensory systems to see true properties of objective reality? Whatever percentage you would assign, one can't deny that this is an interesting, (and valid), question.

Two of the biggest problems that I have with with what Hoffman suggests, (aside from the fact that, despite not being best adapted to perceive things occuring on scales which did not impinge upon our immediate survival, one would expect us to have some fairly clear and consistent programming when it comes to the goldilocks zone of which our conceptual umwelt is comprised - or at least, I, in my recalcitrant ignorance, continue to cling to this notion) 1.) I cannot see how this theory is falsifiable, even in principle. 2.) It doesn't seem to provide the possibility of any testable predictions.

The claim that how we perceive reality is different from how reality really is, is not remarkable. Hoffman's idea that we evolved to experience a collective delusion, is, in a trivial sense, manifestly true. We are privy to a thin slice of the electromagnetic spectrum without the aid of technology. We are led astray by hallucinations which exploit, (either accidentally or intentionally), shortcomings in our perceptual/cognitive systems. etc. It is quite a common view in neuroscience and psychology, and is supported by a lot of evidence. But the additional claims which Hoffman makes go much further than this, and, at least for the moment, I am unwilling to follow him into the depths of what appears to be an empirical argument for transcendental idealism.

With all that being said; this gets my highest recommendation. If for no other reason than how much it has made me think. 

Original Review:

For a review of a book titled The Case Against Reality, one might assume that a drug related tangent would be unnecessary and self indulgent. And yet...

Do you wish to descale your solipsistic leanings of the crusty patina which has effaced their luster with shades of oxidative mockery? Then you should give this book a good tug and spray your militant subjectivity with Hoffmann’s salty lemon juice. Have you ever, in a near fatal incident of gastric incredulity, mulched and composted an entire Salvia Divinorum plant (under the perfectly reasonable assumption that parsley and feta grow in the wild) utilizing your recently implanted tribosphenic teeth and the hollow organs of your GI tract to emulsify your spirit with psychedelic molecules, whilst clutching your head and shrieking. “My skull enshrouds my brain in total darkness, like a casket!”? Then your unique circumstances have prepared you well for the buffet of bizarre notions on offer here.

This book takes the well worn concept of our perceptual systems assembling only crude approximations of reality and amplifies these theories in a manner that would satisfy Nigel Tufnel (i.e. turning it up to eleven). If you had assumed, like me, that, despite its approximate nature, our concepts of the world and the objects that gild it are, at least, somewhat veridical, moisten another blotter with the blind worm in its cave of teeth and think again! We are quickly disabused of the common sense notion that apprehending the truth of ones environment is roughly compatible with maximizing genetic fitness. Instead, we are presented with the case that truth and fitness are mutually exclusive goals in our evolutionary history. Selection pressures are uniformly against truth, and fully in the corner of a fitness divorced from it.

The central idea of the book is called The Interface Theory of Perception, and the gist is as follows: Like a computer icon on your screen of some arbitrary shape and color, the characteristics of the icon itself bears no relation to the files it points to. We are invited to analogize this with how we perceive tomatoes, apples, snakes, orangutans, belligerent gophers, radioactive hobo-scorpions with shotguns, and even space-time.

To say that I didn’t find the arguments for this view entirely persuasive would be to undersell the skepticism I washed them down with. It was a bit like taking sips of brandy and chasing it with chemical cleaner. Cautionary notes are sounded throughout the book to assure us that we’re not descending into metaphysical solipsism, and yet, almost every step of the way I could feel a gulf opening up beneath me, causing me, at various points, to accost strangers with the following lines; “This cosmic dance of bursting decadence and withheld permissions twists all our arms collectively, but if sweetness can win, and it can, then I'll still be here tomorrow to high-five you yesterday, my friend. Peace.”

The book veers between the interesting ways in which our perceptions fail in the edge cases of trying to intuit the phenomena of the very small, the very fast, and the very large - to hacking away at the macroscopic reality of the Dragon Glue (Bad Dragon’s official one-component adhesive used for repairing torn silicone toys), like a Copenhagen Interpretive Axe Murderer.

That’s not to say that I didn’t find fantastic ideas in the book, some of the more tempered speculations were very interesting, and I found some of the anecdotal evidence from the animal kingdom to be pretty neat. Such as Jewel Beetles forgoing reproductive opportunities in order to seek the super stimulus of beer bottles (stubbies) littered across the beach. This had me giggling at the various parallels I conjured up, until I then learned that certain ants had begun to take advantage of this lascivious misfiring and were devouring the poor bastards pecker first, sobering me right up.

Donald Hoffman is obviously a very intelligent researcher who has probably forgotten more than I’ve ever learned about cognitive science, so there’s the very real (or is it?) possibility that my ignorance is keeping me from fully taking these insights on board. I’m not equipped to argue against him point by point. I think, validity of the claims aside, the biggest fault of this book is a schizophrenic use of language. Sometimes reasonably suggesting that there is an underlying objective reality we can understand, but our senses, as a result of computational bandwidth, hide it’s true complexity. Other times pursuing arguments against the notion of causality in deadly earnest. The author seems to have made up his mind on this issue, unfortunately, the book hasn’t.
Profile Image for Ryan Boissonneault.
202 reviews2,163 followers
August 19, 2019
Despite centuries of unrelenting scientific progress, the problem of consciousness remains unsolved. How subjective experience can arise from the electrochemical irritation of nervous tissue remains one of the deepest mysteries of the universe.

But according to Donald Hoffman, we have yet to solve the problem of consciousness—not because we lack data or the intellectual capacity—but because our conception of reality is entirely wrong. Once we come to grips with the true nature of reality, the problem of consciousness can be solved.

The first thing to note is that, while this book may entirely transform the way you see reality, the ideas are not new. Hoffman’s “Interface Theory of Perception” is in many ways a re-statement—supported by research in cognitive science—of Imannuel Kant’s transcendental idealism (Hoffman does give appropriate credit to Kant). In the Critique of Pure Reason, Kant claimed to have achieved a “Copernican revolution” in thought by inverting the traditional relationship between subject and object.

According to Kant, objects in the world (things-in-themselves) provide the sense data that the mind uses to construct its perceptions and ideas of those objects in pre-configured ways. However, the ideas of the objects are not the objects themselves, and since we can only experience the world through our perceptions and ideas, we can never get outside of our own minds to discover the true nature of those objects. Our minds are not passive observers of an external reality but are actively involved in the construction of our own reality.

Hoffman is essentially claiming that the latest research in cognitive science and perception—and even in quantum physics—vindicates Kant. Hoffman, of course, provides details from cognitive science that Kant could not have had access to, but the larger point remains the same—that what we perceive is a construction of the mind and that objective reality, which must exist for the mind to perceive anything at all, is fundamentally different from what we directly perceive. Hoffman introduces the evolutionary concept of “Fitness Beats Truth” to show that evolution almost certainly sculpted our minds for fitness, not to accurately represent reality, thus creating the mismatch between “things-in-themselves” and our perceptions of them.

Hoffman uses the analogy of a computer desktop. Our computer files may be represented by icons that occupy space and take certain shapes and colors, but the files themselves do not sit in the middle of our screens or have any shape or color. The files are, at bottom, bits of information and electrical currents in our computer’s memory; the icons allow us to work with the files in an intuitive way but do not represent the underlying reality of the file.

In the same way, consciousness is a three-dimensional virtual desktop that allows us to interact with the world in useful ways but does not accurately represent the underlying reality, whatever that reality is. Hoffman uses convincing examples throughout the book to demonstrate that things like color are not inherent in objects themselves but are active constructions by the mind in response to certain wavelengths of light. In an interesting case study, Hoffman shows us that if the area of the brain that processes colors is damaged, color can disappear entirely from conscious awareness.

The implications of this—if Hoffman (and Kant) is right—are huge. It means that all natural science is essentially reduced to psychology. A deeper understanding of the material world—including both macro-level objects (including brains and neurons) and quantum particles—are simply icons and pixels in the interface of our consciousness. They tell us nothing about objective reality, only about our interface.

Here’s another way to think about it: an expert Minecraft player that is very good at manipulating and controlling the Minecraft world remains entirely ignorant of the underlying computer code and hardware running the game. Likewise, scientists may have expert knowledge of our virtual interface of the world, but, like the Minecraft player, they have no access to the underlying reality that makes the world of conscious perception possible. This inversion of subject and object also explains why quantum experiments are so dependent and influenced by observation—quantum particles are not the deepest components of objective reality, they are the pixels of our conscious interface that the mind creates.

Kant would agree with all of this, but Hoffman wants to go further than Kant. Kant would see the Interface Theory of Perception as defining the limits of human understanding, in that we simply can’t transcend the limits of perception to see the ultimate cause of our perceptions. Stated in another way, the fundamental nature of reality is about as discoverable as a new color you’ve never seen.

But Hoffman, for some reason, refuses to accept this. He thinks that the ultimate nature of reality can be discovered scientifically and that it is essentially composed of conscious agents. According to Hoffman, we have yet to solve the mystery of consciousness—not because we’re awaiting new scientific discoveries or have reached the limit of human understanding—but because our entire conception of reality is wrong. Once we understand that the world is composed of conscious agents that ultimately create spacetime and all the objects contained within it, we can finally solve the hard problem of consciousness.

I’ll admit that I found this argument to be less persuasive. I think that Hoffman has discovered, like Kant, the boundaries and limits of human understanding. We can investigate the world scientifically as its presented to us, but we have no conceivable way to transcend the limits of our own virtual conscious interface. The things-in-themselves, the objective reality that must exist to provide sense data to our minds, cannot be investigated directly because whatever data we acquire will always be filtered through perceptual systems that we can’t control or transcend. It’s like being born blind and trying to understand what it’s like to see color.

Some readers may be persuaded by Hoffman’s argument, but I don’t see a way around this. If perception is created by the mind based on an objective reality that is different, then we simply have no way to access to this objective reality. It’s what Wittgenstein meant when he said that what can be said can be said clearly, and “whereof one cannot speak, thereof one must be silent.” We can speak about our conscious interface (science and human behavior and experience), but when we attempt to transcend the interface the result is always nonsense. As Kant said long ago, this is precisely the point where we’ve reached the limit of human understanding. Hoffman thinks otherwise; who is ultimately right the reader is left to decide.
Profile Image for Tom Quinn.
586 reviews193 followers
December 13, 2021
What we find here is a bit like H.P. Lovecraft minus the more horrible of the cosmic horror. Heres the gist: we filter reality. Knowing what exists independent of our senses is impossible, and I'm never really seeing objective reality but rather a human-specific interpretation of it. Ah well, c'est la vie! — or a close enough facsimile of it, at least. It's the sort of thought experiment that is sure to shake things up in academic circles where brainy folks cook up theories of everything, but which impacts my daily life in laypersonland not a whit.

3 stars. It's nice to take your brain down less-frequented alleyways and rough it up now and again. The book is pretty short and decently engaging throughout. Hoffman puts in enough flourishes to add occasional levity and flair, but often falls into a repetitive drone of info already shared previously.
Profile Image for Chad Gayle.
Author 4 books68 followers
March 20, 2020
The starting premise here is that evolution has shaped not only our senses but how we interpret the data we gather from our senses. Not a great leap, especially given what's happened in perceptual science and neuroscience over the last few decades, although Hoffman acts as if this premise isn’t a prevailing belief among vision scientists (which I doubt is true). Much of the usual evidence in support of this premise, vis a vis optical illusions and the like, is presented (or, to be a bit more blunt, regurgitated in fitful spasms), and then Hoffman goes further.

Hoffman claims that evolutionary "fitness payoffs" are the basis of all of the sensory information we, or any other living thing, can gather. These fitness payoffs represent a means of preserving and extending our genetic heritage and are neither tied to nor reflective of Objective Reality, which, Hoffman says, is reflected in a mathematical theorem he’s devised, the FBT Theorem. This idea is stated and restated a nauseating number of times, so I understand why other reviewers have complained about the book being repetitive. But it gets worse: Hoffman then takes this idea to such an extreme that he runs his argument off the rails, ditching it in a valley so deep it can never be rescued.

"...the idea that physical objects are just ephemeral data structures that describe fitness payoffs differs sharply from the idea—now standard in vision science—that physical objects are elements of objective reality, and that the goal of vision is to estimate their true shapes and other physical properties."


So it isn't merely that our interpretations of sensory data are "ephemeral data structures" not truly representative of Objective Reality, but that there is no such thing as Objective Reality. According to his FBT Theorem, there's no way for perceptual systems to represent Objective Reality, and therefore, the Objective Reality that we believe in does not exist. He tries to make this point, again and again, by saying that even if we look up at the sky and see the moon, when we look away, the "moon no longer exists." Not in the sense of a baby looking away from something and not understanding object permanence—no: there really is no moon.

If this sounds absurd, it is. Hoffman tries to argue ontologically and philosophically in favor of this absurdity, but there is no actual science (and no proposed experiments or existing experimental data) to back up this conclusion. And then he goes even further, and it gets worse, because he thinks he can lean on quantum physics, that netherworld of neither here nor there, for support of said absurdity.

Now I am not trying to be flippant, but how is it possible that a professor of cognitive science who has had papers published could so fundamentally misunderstand quantum physics? In chapter after chapter, Hoffman tries to suggest that because current interpretations of quantum theory imply that spacetime isn't what underpins Objective Reality, there is no Objective Reality, and his FBT Theorem must be correct. Doesn't Hoffman know what decoherence is? Doesn't he understand that decoherence is one of the reasons I can't be in a superposed state of existence, existing in New York and in the star system of Alpha Centauri simultaneously? Quantum systems decohere not only when they are measured but when they interact with the world around them (Objective Reality). That's why classical physics works the way it does (for the most part) when we zoom out from the quantum world—because of decoherence.

Our senses work in that zoomed out world, not on a quantum level. So it isn't just specious to try to make arguments about whether we are sensing Objective Reality by referring to quantum theory, it's just wrong-headed and, forgive me, stunningly stupid. Our "fitness payoffs" aren't based in the world of the quantum: they are based in the world that arises from the quantum as quantum states decohere. Therefore our "fitness payoffs" reflect our existence in a world where such quantum effects as entanglement are negligible or non-existent.

I'm not suggesting that there aren’t "fitness payoffs" tied to the "ephemeral data structures" in our heads, nor am I claiming that those data structures DO represent Objective Reality. What I'm saying is that a statistical theorem (Hoffman's FBT Theorem) not tied in any respect to physics cannot prove that Objective Reality does NOT exist. The moon is there when we don’t look at it, regardless of what Hoffman wants us to believe.

I wish it ended there, but it doesn't; it gets worse. In the last chapter, Hoffman tries to tell us what reality actually is, since Objective Reality is simply an aggregation of evolutionary fitness payoffs. His answer? Conscious agents, and another (even weaker) mathematical theorem.

That's right: the moon isn't there, because we live in a universe of conscious realism. There is no spacetime; there is only consciousness.

The expression "Come back down to Earth" seems fitting here.
Profile Image for Brian Clegg.
Author 214 books2,876 followers
August 21, 2019
It's not exactly news that our perception of the world around us can be a misleading confection of the brain, rather than a precise picture of reality - everything from optical illusions to the apparent motion of video confirms this - but professor of cognitive science Donald Hoffman goes far beyond this. He wants us to believe that spacetime and the objects in it are not real: that they only exist when we perceive them. It's not that he believes everything to be totally illusory, but suggests that the whole framework of the physical world is a construction of our minds.

To ease us into this viewpoint, Hoffman gives the example of the Necker cube - the clever two-dimensional drawing apparently of a cube which can be seen in two totally different orientations. Calling these orientations 'Cube A and Cube B' he remarks that our changing perceptions suggest that 'neither Cube A nor Cube B is there when no one looks, and there is no objective cube that exists unobserved, no publicly available cube waiting for all to see.' Yet surely this is disingenuous - there never was any cube, it's a two-dimensional drawing. There is no physical object.

Hoffman provides us with a good and interesting simile in the idea that our perception of the world stands in relation to reality rather in the same way that a graphical user interface does to the underlying bits and bytes in a computer (even if we do then suffer repeated Matrix references, which feel a bit dated these days), and we get plenty of good material on the limitations of the senses - but the extreme conclusions, dragging in evolution and the idea that objects don't exist if we don't observe them feels like an attempt to give a notion a lot more depth than it really has.

It seems pointedly misguided to posit that nothing exists when we don't construct it, then to give examples from 'nature' as if such a thing has an independent existence in this worldview. This contradiction comes through particularly strongly when Hoffman refers to black holes, something we have never directly observed and so, according to his argument, can't exist. Throughout there seems to be a a lack of distinction between models and reality.

From the physics viewpoint, there is a big red flag suggested by having the lead puff on the back of the book written by Deepak Chopra. In fact there is a distinctly Chopra-like attempt to align a theory with quantum physics without any scientific basis: the quantum physics that Hoffman describes seems to assume that quantum particles are constantly in states which are actually fragile and unusual as a result of particles interacting with their environment, causing decoherence. Quantum theory is no help in supporting these ideas of a world created by the observer. Perhaps the clearest example of a lack of understanding of physics is in the statement 'The interface theory predicts that physical causality is a fiction. This is not contradicted by physics.' Unfortunately, it is. Relativity certainly does away with the concept of simultaneity, but this does not mean that causality goes out of the window.

This remains an interesting, if frustrating, book, but it does feel very much like an attempt to construct a castle in the air. The emperor may have some clothes, but they're very skimpy.
Profile Image for Vagabond of Letters, DLitt.
594 reviews327 followers
April 8, 2020
It's social constructionism taken to its logical conclusion via evolutionary theory (which is normally anathema to constructivists). The interest here is in finding an attempt to reconcile constructivism with the 'objective truth' of evolutionary theory - but if this book's thesis is correct, evolutionary theory is not true, or at least it's impossible for humans or other evolved agents to know if it is or isn't. If the author's thesis is true, it's impossible for us to know that it's true, or to predicate truth of anything. So if the author is correct, we have no grounds for believing him, nor for predicating 'correctness' of any idea, including his own. This is deeply self-referentially incoherent, radically corrosive skepticism which results from taking the other horn of the dilemma of Platinga's Evolutionary Argument and goring oneself on it.

I'll remain a realist-essentialist.
Profile Image for Ms. Smartarse.
630 reviews315 followers
August 20, 2022
I'm guessing that by now we all know that our perception of the world is not quite accurate, however do we know just how off we truly are? According to Donald D. Hoffman: COMPLETELY. And that's good, because humanity's survival depends on a fitness-based perception, rather than an accurate one.

I don't know anything

Now normally, I would never voluntarily read this type of scientific non-fiction, but I had promised myself to give book-club suggestions a decent try... and finish reading them whenever possible. So here I am!

Things start out well enough, with very simplistic (if creepily intriguing) examples of brain surgeries improving the life of epileptics. It then takes a gentle turn into questioning the nature of human (and occasionally animal) perception, only to suddenly come to the conclusion that not only is it wrong, but quite possibly also irrelevant outside of active observation? That being said, we are insistently warned to heed our survival instinct and not jump in front of a speeding car.

swerving children's car

Unfortunately, in the end things started getting a bit too convoluted for my attention-span. By which I mean, that I could probably have found a Youtube video or two to better explain the theory being referenced, but... I was too lazy to look. Then again, I'm also the type of person who's not that bothered when advanced scientific concepts just pass me by. Well... not always.

Score: 3.3 / 5 stars

On the whole, I believe my attitude going into the book may not have been the right one. Instead of just curiosity, I could have benefitted from a more inquisitive mindset which would've propelled me to actually research some of the more advanced concepts being referenced. Alas... I'm just not that interested. Still, some of it caught my attention, such as the Necker cube experiment, and I spent several cross-eyed minutes replicating it.

Necker cube

So if you enjoy reading about experimental scientific theories, and are up to snuff on your quantum physics theory, by all means give it a go. Otherwise... start with the first two chapters, and see how you feel about it.
Profile Image for Aerin.
152 reviews552 followers
March 5, 2020
So, this book took me off guard a bit, because I was expecting it to focus on how limited our senses and cognitive processes are. Just because we see color doesn’t mean there’s not a whole range of the electromagnetic spectrum we’re blind to; just because we think we understand something doesn’t mean we’re not relying on a bunch of misleading heuristics, that kind of thing. And Hoffman does discuss some of that stuff, but he goes SO MUCH FURTHER, ultimately claiming that spacetime itself is just an interface constructed by conscious beings that has very little connection to “objective reality,” whatever that might be. He pulls in not just philosophy and neuroscience to back this idea up, but invokes the many unsolved mysteries of quantum physics as evidence that spacetime itself is an elaborate illusion.

And I mean, okay. Who knows. Brains in jars and all that. By the time he was overthrowing all of “physicalism” in favor of his theory of conscious agents as the fundamental particles of reality, I was just kind of shrugging and saying “sure man, let’s see where this leads.” And ultimately, it doesn’t lead much of anywhere except to a whole lot of quotes from The Matrix. But still! Four stars to this book for being so ballsy and genuinely blowing my mind a little bit. Because, while I do think his ontology of conscious agents is almost definitely full of shit, it’s an interesting idea to play around with. And Hoffman isn’t coming at this from a pseudoscientific, new-agey, or religious point of view, at least most of the time. He grounds his ideas in science, so it’s difficult to completely dismiss him as a quack. So, I don’t know. An interesting read.
Profile Image for Atila Iamarino.
411 reviews4,428 followers
October 18, 2019
Uma ótima surpresa. Escolhi ouvir esse livro meio que na dúvida ainda, achando que seria mais um livro sobre sentidos e evolução. Foi bem mais do que isso. Acabou sendo o melhor argumento que já li de como nosso entendimento do mundo é limitado e porque vivemos em um universo holográfico.

O Hoffman faz um passeio por como o que a evolução seleciona são organismos capazes de entender o mundo o suficiente para sobreviver, e não organismos com um entendimento completo do que é a realidade. Em seguida ele parte para as propriedades físicas do universo e como o princípio da incerteza de Heisenberg nos impede de saber tudo sobre o universo. Uma mistura de conhecimento bem pesada, mas legal quando costurada junta. Espero que a explicação física/quântica do universo esteja correta, a parte biológica estava bem situada.
Profile Image for Muwaffaq Salti.
173 reviews
August 26, 2019
I would like to give this book 3 different ratings - 3 stars 4 stars and 5 stars. As a novel concept and really original thought experiment it is definitely 5 stars. For interest and some other related novel views as well as some good descriptions of various physics and biological concepts and experiments alongside its' novel themes - 4 stars. However, for the writing and repetition and really cryptic abstract explanations I can only give it 3 stars. I am not the smartest person in the room nor am I the dumbest but I found it really really hard to follow large passages in this book. I am not even sure if those explanations added any lustre to his overall argument. On top of that, whilst what he says makes sense at a very high level, I am sure a physicist or biologist could equally plausibly argue against his main idea and I would be none the wiser. Finally it ends extremely abruptly, just as I am wondering what experiments we can do or what lessons I can take from his main thesis. Perhaps I should have given it 2 stars..........
Profile Image for Buck Wilde.
899 reviews54 followers
August 3, 2021
"If a tree falls in the forest, and nobody hears it, did it make a sound?"

Now take that sentence and stretch it out into an agonizing, 400 page self-congratulation penned by an uncharming Frasier using the biggest words and most circular arguments he can muster. Sprinkle in a fart-sniffing reference to his own research every three paragraphs or so, and you've assembled this horror.

If you want the same content but to spare yourself the trauma of trying to trudge through the masturbatory jargon, find a white guy with dreads outside of a music festival and promise him ketamine if he can summarize an Intro to Evolutionary Biology textbook.
Profile Image for inf.
5 reviews
August 5, 2020
I am sympathetic to the author’s general thesis, hence this book was disappointing not because of its conclusions (to which many reviewers objected) but because it did a poor job of making its case both in its arguments, and in its style and approach.

The principal arguments in this book attack naive realism. The author seems to favour a sort of Kantian position where objective reality is not knowable, but goes a step further and claims that reality has no resemblance to the world we perceive, denying even space and time (which Kant believed to be known a priori). In this regard his view is sometimes closer to Berkley's subjective idealism (reality exists only in our minds). The main thrust of the argument is based on the theory of evolution: since natural selection favours fitness over truth, our senses have developed to aim for a picture of reality that ensures survival rather than accuracy. A recurring metaphor is that of the computer interface – the mail icon that we see on the monitor does not accurately correspond to the transistors or bits that constitute it in 'reality'. Most of this I can accept, but the book has many problems and I will devote the rest of the review to discussing them.

The book opens with the cliche of Galileo's condemnation by the church. This is a red flag, since the affair is usually retold by authors who believe themselves to be revolutionaries whose only source of disagreement is your obstinate dogma. Usually it's the author who's fooled themselves into thinking they've discovered a radical truth. I continued reading, and my suspicions were confirmed – there are few original arguments in this book; the majority of it is spent reiterating now-banal ideas and anecdotes you've most likely read before if you have any interest in this topic. The author restates theories from very popular books (the likes of Dennett, Dawkins, and Trivers) and borrows heavily from them without adding much other than hype, superfluous examples, and pointless commentary. At one point I had to check the publication date, incredulous that the book was published in 2019 and written with a tone that implied novelty.

The first part of the text tediously explains the development of our perceptions through the evolutionary process, with the underlying theme being that they do not give us an accurate picture of reality. Given the author's definition of 'accurate' – we are susceptible to optical illusions, for instance, and can't directly perceive the majority of the electromagnetic spectrum – this is something most of us would concede. But instead of making the point and moving on, the author decides to survey the literature, illustrating the concept with overused examples like Necker cube, prisoner's dilemma, and neurology cases you read about in Oliver Sacks stories. The general conclusion here is that 'fitness beats truth': adaptation has selected against truthful perception in favour of perception which confers a competitive advantage. Several chapters are spent presenting a mishmash of tenuously related examples and cherry-picked quotes from big names which purport to evidence the claim.

The problem is not so much that the author doesn't make an effort to be original or that these examples can be found elsewhere. It's that (1) the author likens this work's ingenuity to that of Galileo's, and (2) the title of the book is 'The Case Against Reality', not 'A Compendium of the Failures of the Evolutionary Process to Develop Accurate Sense Perception', and yet the majority of the book is not devoted to arguing the case. There is also an unhelpful focus on refuting the straw man of 'veridical perception' (the idea that our senses match reality exactly) which I don't think anyone actually endorses. In general the author provides extensive reasoning for the easy claims but glosses over the hard ones. Being generous I might presume an editorial choice was made to simplify the explanations, garnish the narrative, and add a sprinkle of pop-culture references (The Matrix is frequently quoted and alluded to) to make it more palatable for a general audience, but clearly this failed since all it achieved was making the book less compelling and more frustrating.

The second part is the author's philosophical interpretation of the facts. The style continues to be blandly self-promotional and the arguments unconvincing. For instance, he explains Plato's allegory of the case but writes that his theory is much more radical: our perceptual world is not even close to a shadow of the objective world. There are no arguments, only assertions feebly connected to the findings from earlier chapters. An apparent contradiction emerges here: the author denies that our perceptions (including those from our scientific experiments) have any basis in reality, yet he uses them to construct a theory about reality. A single paragraph is devoted to dispelling this problem and it sounds something like 'yes all of our perceptions are useless but no the cognitive faculties that I'm using to make this theory are totally fine'. There is also a big jump from 'fitness beats truth' to 'there is no relationship between perception and reality'; no convincing case is made for the idea that natural selection ignores the real world entirely to construct a model in our minds that improves fitness. In fact, once the author has presented the various scientific findings, he resigns to arguing anything and simply assumes that whatever he has said is correct in light of those facts.

We're now two thirds into the book and finally something interesting appears: an alternative theory of perception. The basic idea is that perception applies two algorithms to incoming data. One is a compression algorithm that ignores everything that isn't useful for survival and reproduction. The other is an error-correction algorithm which adds redundancies (e.g. extra dimensions) to help improve the integrity of fitness-related details of reality. Together they render the three dimensional temporal world we experience. I'm not sure if I buy the connection to the earlier stuff on the holographic principle, Hawking radiation, and entropy in black holes – in fact, the quantum mechanics chapter is the most dubious in the entire book – but it's an interesting train of thought. It's far from a scientific theory but if the book devoted more time to expounding this idea it could provide some inspiration at least.

The final part addresses consciousness. The theory presented falls in the monistic idealism class – 'conscious agents' are the fundamental substance, and the 'physical' world exists only in the experiences of these agents. This reverses the physicalist conception of consciousness by turning the material world into a by-product of conscious experience, rather than positing consciousness as an emergent property of the physical world. As the author admits, aspects of this theory appear all over philosophy from as far back as antiquity, but he claims his formulation is precise and scientifically testable. I'm not so sure.

Other general issues with the writing is that (1) it's very repetitive – the author sometimes spends several paragraphs rephrasing the same minor point, only to do the same again in a different chapter like a maths teacher trying to drill in the times tables; (2) there are many factual errors, some of which are minor or irrelevant (wrong dates, discoveries attributed to the wrong person) but careless mistakes like these make you question how much of this text you should take seriously; (3) the frequency of unnecessary tangents and lack of structure make the overarching narrative difficult to follow. This might be forgiven if the anecdotes were interesting but the book really needed better editing to prune irrelevant and repetitive passages.
Profile Image for Jan.
129 reviews5 followers
September 22, 2019
For people who are unfamiliar with epistemology this book can be like the red pill in the movie The Matrix. It’s in the same category as Robert Lanza’s book Biocentrism and Bernardo Kastrup’s scientific take on philosophical idealism: The Idea of the World. Except that Hoffman’s book approaches the issue from evolution theory. A universal acid, Daniel Dennett has called it. In fact it’s much more so than Dennett imagined. It even dissolves the claim that objective reality consists of spacetime and objects, including such things as DNA, organisms and brains.

To what extent does the totality of our experience, our perception, show us what objective reality, independent of our observation, is really like? Perception has been shaped by evolution by natural selection. Many people, among them biologists and cognitive scientists, think that to survive and procreate organisms must have a perception that resembles objective reality as much as possible. But they’re wrong.

Donald Hoffman and his team have carried out extensive research using computer simulations, often involving genetic algorithms, that show that perception that is tuned to resemble reality loses out to a perception that simply shows an efficient interface made up of virtual reality that improves the organism’s chances of survival and procreation, whatever reality is really like. You might say our reality shows nothing but 'fitness points'. As Hoffman says: fitness beats truth every time. Even in the case of a reality with only a few aspects the probability that perception shows truth is almost zero.

A good analogy is a PC desktop with icons. Spacetime is the desktop, and physical objects, or ‘matter’, are the icons. They don’t look anything like the actual reality of silicon circuits with tiny transistors and voltages in the computer, and they don’t need to. They even shouldn’t. Instead they’re an excellent user-interface with that reality.

Hoffman gives many examples of cognition and illusion to show that our perception of space, time and matter is a construction in our consciousness, just as philosophers have been telling us for thousands of years. He also points out that physics just tells us how the interface behaves. It doesn’t tell us what fundamental reality is. In fact quantum physics, relativity theory and the holographic principle appear to show that the interface is a kind of informational hologram that depends on observation. At any rate, many physicists are coming to the conclusion that spacetime is not fundamental, but emerges from the quantum vacuum.

It’s as if every conscious agent is wearing a VR headset shaped by evolution. The virtual reality that they’re creating is not reality itself. This is also true for the brain, and for neurons. These are also just icons constructed by consciousness, so they can’t produce consciousness. This explains why physicalism has what is called the hard problem of consciousness. There is no way that brains could ever produce, or be, consciousness. They’re simply desktop icons, like faces, of the conscious agents ‘behind’ them. Not 'matter' but consciousness is fundamental.

Philosophers have mostly said that real, ultimate reality is forever beyond our reach. Certainly Kant said this. Some have said the only way to catch a glimpse of it is by mystical experiences. Hoffman however thinks that this fundamental reality, which is a network of interacting conscious agents, can by expressed by mathematics, which should eventually show us how quantum physics, spacetime, physical objects and the laws of nature are constructed in our interface. In this way it would come within the grasp of scientific inquiry. This is highly ambitious to say the least. But then again: science should be ambitious.

Hoffman has done a TED talk in 2015: 'Do we see reality as it is?', which is available on youtube. If you like that talk, you will definitely like this book.
Profile Image for Paul.
62 reviews1 follower
December 4, 2020
"What if, right, what we see isn't really reality and it's all an illusion?"
"Whoah, you mean like the Matrix?"
"Yeah, exactly. "
"Dude, you're smart, you should write a book about it!"
"It's not really enough to fill a book though."
"Just keep repeating yourself and mention The Matrix a lot. People love the Matrix, you'll seem really cool."
"Maybe, still doesn't seem like enough for a book though. I could add in an optical illusion or too to make the point that our senses aren't infallible."
"Add in loads of them! Multiple chapters of optical illusions, no matter how irrelevant or tangential. People love optical illusions!"
"Dude, I think we have ourselves a book!"

A couple of interesting ideas in here, but just ideas with nothing to back them up.
Profile Image for Andrew Kitzmiller.
27 reviews2 followers
September 7, 2019
I understand the argument that we do not perceive reality completely, but the leap to conscious realism seemed unwarranted and unconvincing.
Profile Image for Kunal Sen.
Author 27 books52 followers
January 22, 2020
I thoroughly enjoyed the process of reading this book, because it made be think all through, but in the end, I could not agree with what it was trying to say.

The author uses game theory and mathematical simulation to understand how evolution shaped our perception of reality. He claims that we evolved to create a perceptual mechanism that is not trying to model the physical reality, but rather it creates an interface through which the physical reality is mapped into our perceptual world model in order to maximize our fitness — that is our ability to make babies and to take care of them.

The traditional view of visual perception believes that our visual mechanism approximates the physical reality, and in higher animal the process is fairly accurate. That is, what we see is very close to the physical reality. The author is challenging this view. According to him, and based on a few game theoretic things he and his colleagues have proved, the claim is that the probability that a higher evolved perceptual mechanism will reflect reality is vanishingly small. In other words, our perception does not capture reality at all. He then extends this to say that our view of space and time is all an artifact of our perceptual system, and the physical reality perhaps has neither space nor time. To support this fantastic claim, he is delving into modern physics, where there are questions about the fundamental nature of reality, which is also sometimes highly nonintuitive.

I love challenging ideas, but his claims seem implausible to me. Here is a few thought experiments to challenge it.

Let’s say I am perceiving I am in an empty room and there is a solid cube one meter away. My visual system is telling me so, which he believes is an artifact created by our cognitive interface. That is a fair assumption. Now let’s say I use a long stick, close my eyes, and try to probe the object with my stick and try to guess the position and shape of this object. Again, my conclusion will be identical to what I saw. The author would say that the interface is still fooling us because it created a self-consistent model, no matter with perceptual mechanism we use. Now let’s say I use an electronic echo device using ultrasonic sound to map my surrounding. Based on the time it takes the reflection to come back I can once again determine the position and shape of the object, and I will get the same answer. Now the author will have to say that the interface that evolved over millions of years of evolution also made provisions for this electronic probe and made sure our illusion is maintained. No matter which cutting-age tool we use to measure the position and shape of this object, the answer will always be the same, and somehow evolution anticipated all these modern innovations and adjusted for each. This is almost absurd to me, rather than assuming that the interface is not reality, but it is approximating the physical reality, and that is why there is such agreement between the different measurements, irrespective of the mode of measurement.

When the author claims that some modern physicists are close to abandoning space and time, he is once again making a strange leap. All that physics might me saying is that space and time may not be fundamental concepts, and there is something deeper that creates space and time. There was a time when we believed atoms are fundamental particles. Eventually we discovered that there are more fundamental building blocks. Discovery of protons, neutrons, and electrons did not make atoms vanish, but just robbed its fundamental status.

It is also strange that while the author is claiming that space, time, and objects do not exist and are just artifacts that our conscious mind creates, and yet he is constantly referring to and arguing with physical objects such as the brain, nerves, and all sorts of objects that live in space and time. While talking about color and color perception he is talking about electromagnetic waves and frequency, but how can there be frequency without the concept of time? That is, he conveniently uses physics based on space-time and then tries to prove that it is not real.

He then proceeds to explain consciousness based on his previous ideas and dismisses any possibility that physical systems can ever explain consciousness. That is again a strange claim to make when any serious scientific enquiry into this area is fairly recent. It is like dismissing the possibility that we will ever understand why the sun is hot in the 15th century. In reality a lot of interesting possibilities are opening up and there is no reason to believe that we have exhausted all avenues of research.

Here is an interesting case of a very smart person coming up with an interesting idea, and then falling so much in love with this idea that he is trying to twist things to fit this world view even when there are perfectly good alternatives available. I would still recommend my friends to read this book because it raises very interesting and tantalizing questions in many disciplines.
Profile Image for Richard.
Author 1 book48 followers
March 28, 2024
Our picture of the world—the way it appears, for example, if you glance up for a moment from this book review and look around at wherever it is you happen to be right now—is plainly very different from the way it actually is. I think I was around twelve years old when I first realised this myself, at school just looking at one of those wall-posters with radio waves at one end, gamma rays at the other and that narrow coloured band of “visible light” arbitrarily set in the middle: first, just how little of what there is, how thin a sliver, we see; and then, that much the same is true for sounds, scents, touch and all the rest. The “world” as we experience it is an accurate, but severely reduced, simplification.
    The Case Against Reality is an odd book. For a start, reading it I had the feeling that Donald Hoffman is setting up a straw man here, then knocking it down, setting it back up, knocking it down again… His claim is that most people think their picture of reality is a true one (“veridical” is the word he uses endlessly), then he can demolish this and tell us how wildly wrong we all are. But how many of us believe this in the first place? The overwhelming majority of human beings are not reflective enough (or far too busy more like, feeding the kids, doing a day’s work, worrying about the bills, their health, the planet) to have ever given the matter any thought. And of those who have, do any of us believe we’re experiencing things exactly as they are?
    Then there’s the conclusion the book turns out to be heading towards (in perhaps the final ten pages or so out of two hundred). This is something he calls “conscious realism”, which as best as I can understand it seems to be a form of idealism (in the Bishop Berkeley meaning of that word): “consciousness, not spacetime and its objects, is fundamental reality and is properly described as a network of conscious agents”.
    Finally, there’s the endless repetition, which soon gets pretty tedious. I may be quite wrong about this, but it crossed my mind that, his ideas having already been savaged by fellow academics, this book was aimed at convincing them rather than the rest of us. The repetition also had me wondering whether he fully believes his own ideas; it almost sounded as if he was trying to convince himself as well. He didn’t convince me.
Profile Image for Ed Kless.
Author 3 books16 followers
September 11, 2019
I first became aware of Donald Hoffman's work via YouTube suggested video a few years back. This book is the culmination of over a decade of his thinking starting with him trying to better understand human visual perception and leading to him questioning what we think of as reality.

This book dives deep in two of his major hypothesis. First, the Fitness Before Truth (FBT) Theorem which posits that evolution prioritizes fitness for survival in our environment above truth-seeking. Hoffman shares dozens of examples of this. Second, the Interface Theory of Perception (ITP) which posits that our world is more like a desktop interface on a computer with the objects with which we interact mere icons of the true reality. Again, Hoffman shares examples and refutes many objections to this concept.

These two ideas lead to a startling conclusion - the fundamental element of our "world" are not based in spacetime, but rather in consciousness. It is our nature as conscious agents interacting with one another that creates the reality we "see."

Um, yeah, it is hard to wrap your mind around it.
Profile Image for Vander Alves.
262 reviews3 followers
July 15, 2021
Fascinating discussion on perception and reality with lots of ideas to ruminate about, but also plenty of absurd arguments and unwarrented repetition.
Profile Image for Shiva Somadev.
Author 2 books5 followers
May 23, 2020
Let's see what the pioneering science can tell us about true nature of reality. Donald Hoffman is a professor of cognitive science. I hugely admire his work. I mention him and his ideas on true nature of reality in one of the latest chapters "Virtual Realities and the Simulation Theories" in my book "Journey into the Heart of Reality". Although, I have disagreements on certain Hoffman's subjects (specifically an idea of evolution), nevertheless, I think this fascinating book deserves reading.

Below is one of the most useful reviews on this book:

4.0 out of 5 stars Verified Purchase
Reviewed in the United States on August 19, 2019
Investigating the limits of human understanding
Despite centuries of unrelenting scientific progress, the problem of consciousness remains unsolved. How subjective experience can arise from the electrochemical irritation of nervous tissue remains one of the deepest mysteries of the universe.

But according to Donald Hoffman, we have yet to solve the problem of consciousness—not because we lack data or the intellectual capacity—but because our conception of reality is entirely wrong. Once we come to grips with the true nature of reality, the problem of consciousness can be solved.

The first thing to note is that, while this book may entirely transform the way you see reality, the ideas are not new. Hoffman’s “Interface Theory of Perception” is in many ways a re-statement—supported by research in cognitive science—of Imannuel Kant’s transcendental idealism (Hoffman does give appropriate credit to Kant). In the Critique of Pure Reason, Kant claimed to have achieved a “Copernican revolution” in thought by inverting the traditional relationship between subject and object.

According to Kant, objects in the world (things-in-themselves) provide the sense data that the mind uses to construct its perceptions and ideas of those objects in pre-configured ways. However, the ideas of the objects are not the objects themselves, and since we can only experience the world through our perceptions and ideas, we can never get outside of our own minds to discover the true nature of those objects. Our minds are not passive observers of an external reality but are actively involved in the construction of our own reality.

Hoffman is essentially claiming that the latest research in cognitive science and perception—and even in quantum physics—vindicates Kant. Hoffman, of course, provides details from cognitive science that Kant could not have had access to, but the larger point remains the same—that what we perceive is a construction of the mind and that objective reality, which must exist for the mind to perceive anything at all, is fundamentally different from what we directly perceive. Hoffman introduces the evolutionary concept of “Fitness Beats Truth” to show that evolution almost certainly sculpted our minds for fitness, not to accurately represent reality, thus creating the mismatch between “things-in-themselves” and our perceptions of them.

Hoffman uses the analogy of a computer desktop. Our computer files may be represented by icons that occupy space and take certain shapes and colors, but the files themselves do not sit in the middle of our screens or have any shape or color. The files are, at bottom, bits of information and electrical currents in our computer’s memory; the icons allow us to work with the files in an intuitive way but do not represent the underlying reality of the file.

In the same way, consciousness is a three-dimensional virtual desktop that allows us to interact with the world in useful ways but does not accurately represent the underlying reality, whatever that reality is. Hoffman uses convincing examples throughout the book to demonstrate that things like color are not inherent in objects themselves but are active constructions by the mind in response to certain wavelengths of light. In an interesting case study, Hoffman shows us that if the area of the brain that processes colors is damaged, color can disappear entirely from conscious awareness.

The implications of this—if Hoffman (and Kant) is right—are huge. It means that all natural science is essentially reduced to psychology. A deeper understanding of the material world—including both macro-level objects (including brains and neurons) and quantum particles—are simply icons and pixels in the interface of our consciousness. They tell us nothing about objective reality, only about our interface.

Here’s another way to think about it: an expert Minecraft player that is very good at manipulating and controlling the Minecraft world remains entirely ignorant of the underlying computer code and hardware running the game. Likewise, scientists may have expert knowledge of our virtual interface of the world, but, like the Minecraft player, they have no access to the underlying reality that makes the world of conscious perception possible. This inversion of subject and object also explains why quantum experiments are so dependent and influenced by observation—quantum particles are not the deepest components of objective reality, they are the pixels of our conscious interface that the mind creates.

Kant would agree with all of this, but Hoffman wants to go further than Kant. Kant would see the Interface Theory of Perception as defining the limits of human understanding, in that we simply can’t transcend the limits of perception to see the ultimate cause of our perceptions. Stated in another way, the fundamental nature of reality is about as discoverable as a new color you’ve never seen.

But Hoffman, for some reason, refuses to accept this. He thinks that the ultimate nature of reality can be discovered scientifically and that it is essentially composed of conscious agents. According to Hoffman, we have yet to solve the mystery of consciousness—not because we’re awaiting new scientific discoveries or have reached the limit of human understanding—but because our entire conception of reality is wrong. Once we understand that the world is composed of conscious agents that ultimately create spacetime and all the objects contained within it, we can finally solve the hard problem of consciousness.

I’ll admit that I found this argument to be less persuasive. I think that Hoffman has discovered, like Kant, the boundaries and limits of human understanding. We can investigate the world scientifically as its presented to us, but we have no conceivable way to transcend the limits of our own virtual conscious interface. The things-in-themselves, the objective reality that must exist to provide sense data to our minds, cannot be investigated directly because whatever data we acquire will always be filtered through perceptual systems that we can’t control or transcend. It’s like being born blind and trying to understand what it’s like to see color.

Some readers may be persuaded by Hoffman’s argument, but I don’t see a way around this. If perception is created by the mind based on an objective reality that is different, then we simply have no way to access this objective reality. It’s what Wittgenstein meant when he said that what can be said can be said clearly, and “whereof one cannot speak, thereof one must be silent.” We can speak about our conscious interface (science and human behavior and experience), but when we attempt to transcend the interface the result is always nonsense. As Kant said long ago, this is precisely the point where we’ve reached the limit of human understanding. Hoffman thinks otherwise; who is ultimately right the reader is left to decide.
Profile Image for Bookish Dervish.
812 reviews240 followers
June 13, 2020
Quite a read. The central premise of this book is that what we percieve as objective reality is just fitness points directing our behaviour towards surviving and begetting offspring. Basing his arguments on evolution and modern physics. The author presented clear analogies to make his point. The blue icon on the desktop stands for what we percieve (taste, color, shape, direction, speed......) this icon does not show the cilicon circuits, voltages, software....etc.
So, how can we be sure there is a red tomato a meter away when nobody looks?
Hoffman adresses the issue of conscience which is still unsolved by science to this day.
Here is his ted talk discussing the same issues.
https://youtu.be/oYp5XuGYqqY
Profile Image for Michiel.
359 reviews84 followers
March 28, 2020
I find this a difficult book to rate. While beginning reading it, I found its main thesis vague and a bit obvious even. Reality is not what we see, does not everyone with a basic scientific education knows this? At small scales, it is all molecules, atoms and quantum processes while time-space behaves counter-intuitively at galactic scales. We, poor creatures, evolved at the medium size, are not naturally equipped to handle these realities. It is thus evident that what we see is not what there is. For example, everyone would agree that the scent of menthol is something constructed in our minds, not a fundamental property of the molecule.
Hoffman's statement, however, is stronger than merely arguing that there is a mismatch between our senses and the world. According to him, there is no objective reality. There is no moon if you are not looking. Much of the book's argumentation is based on discussing optical illusions and other quirks of our vision system, which feels at times not very convincing.
I had to give it a bit of thought to rate this book. The main point of this book feels at times both self-evident as well as bizarre. However, I did actually enjoy reading it, and many of the ideas and examples were quite impressive. Especially in the last chapter, where Hoffman introduces the Conscious Agent Thesis, which would, in theory, lay a mathematical foundation for consciousness is very interesting.
Profile Image for B.
40 reviews3 followers
June 14, 2020
I really didn't appreciate this book. I went in open-minded and ready to be convinced. In fact, I went into it actually agreeing with the main idea - that our perceptions are a filter through which we see the world. I thought that would be enough to at least get a few nuggets out of the book, but I was sorely disappointed.

I really tried to power through this one, but I ultimately had to DNF it halfway through. Around the time I progressed from rolling my eyes to actually talking at the book, I knew it was time to move on.

Things that made me crazy:
* None of the claims are falsifiable.
* The tone is smug and self-aggrandizing.
* Constant name dropping.
* He uses vocabulary in excess just to sound smart. For example, "Our specious conflation of serious and literal tempts us to reify physical objects and snipe-hunt among our figments for progenitors of consciousness."
* Misrepresentation of objections - He regularly argues against the many objections he has received. But a little bit of research into his detractors reveals that the objections he includes are wildly misrepresented straw men.
* Verbal sleight of hand - He coins a metaphor and names it a theory "for convenience." He then spends the rest of the chapter treating it like an actual scientific theory. It claims, permits, and disallows many things.
* Mistreatment of math - He claims to have figured out a mathematical theorem that he called on someone else to prove for him. But he doesn't even state it rigorously (not even in English, much less mathematically rigorously). And we're just supposed to take him at his word that it proves/disproves all the things he says it does.
* It's so much longer than necessary. This started to feel intentional to take advantage of the fact that people are psychologically predisposed to accept anything that's familiar. If he could just repeat himself enough times, we'd all start to agree with him.
* Nothing he says actually matters. Even if it were true, it wouldn't change the way we live and interact with the world around us.
* Did I mention that none of the claims are falsifiable?

Ultimately, this book is a pedantic philosophical argument dressed up to pretend it's scientific. Philosophy is excellent (when it's actually done well), but it's not science.
Profile Image for Alja.
95 reviews46 followers
August 16, 2019
The author combines evolutionary thinking, quantum physics, philosophy, and more to challenge the assumption that we perceive the world as it is. Through the Interface Theory of Perception, Hoffman redefines our perception as an interface to the world that hides its complexity just like computer icons hide the complexity of their underlying software and hardware. The book is quite a mind-bender, and while there are attempts at making it accessible to a wider audience and even practically applicable in marketing, it is certainly not a book you can casually pick up. That said, if you are itching to go down the rabbit hole after reading about Hoffman's theory, strap in and enjoy the ride.

I loved having my assumptions challenged although the book often left me wanting more; some ideas could have been developed further, and several assumptions were left unchallenged. While the book could use a couple more editorial passes, I found the proposed theory well presented and I'm looking forward to seeing it further developed and studied, especially in the context of consciousness.
Profile Image for Baldy Reads.
123 reviews11 followers
March 9, 2023
While I am interested in Philosophy as a subject, I’m not well versed in it. (Have you seen some of the dissertation-length reviews on here?)

With that said, I think Hoffman did a good job of using common examples while also referencing his own research. However, the middle third of the book became repetitive and at times a bit convoluted—especially his regarding quantum physics. You kinda lost me there buddy.

What I think Hoffman suggests is not that objective reality doesn’t exist, but that we can never see it as it truly is because evolution and natural selection have disguised reality. We see what we need to see—for our own good/survival. (Comment or send me a message if I seem way off.)

Overall, this was an interesting read that got me thinking about weird shit.
Profile Image for کافه ادبیات.
267 reviews101 followers
December 7, 2023
دونالد هافمن دانشمند پیشتاز علوم شناختی و استاد برجسته دانشگاه ارواین کالیفرنیا در کتاب «ادعایی علیه واقعیت» رابطه بین ادراک‌های حسی افراد و واقعیت عینی را به چالش می‌کشد و ادعاهای عجیبی مطرح می‌کند. او می‌گوید تکامل از طریق انتخاب طبیعی موافقِ ادراک‌هایی است که حقیقت و واقعیت عینی را پنهان می‌کنند، و ما نمی‌توانیم به حواسمان اعتماد کنیم که حقایق را درباره واقعیت به ما بگویند. درواقع حواس ما واقعیت را پشت یک رابط کاربری یا همان Interface پنهان می‌کنند، همانند اینکه در این دنیای واقعی یک هدست واقعیت مجازی جلو چشم‌های شماست که از آن بی‌خبرید اما تجربه‌ای جذاب را برایتان رقم می‌زند که به بقا و تکامل شما کمک می‌کند. این کتاب درواقع کمکی برای برداشتن هدستی است که نمی‌دانستید تمام وقت در حال استفاده از آن هستید.
Profile Image for Mark Broadhead.
324 reviews38 followers
July 24, 2021
Tries hard to make arguments, but the author is lacking basic understanding of philosophy (Kant and Berkeley ... mentioned only in passing) and physics (refers to space between nucleus and electron as "empty space").
Profile Image for Finn.
7 reviews
Read
March 25, 2024
I read a couple chapters of this for an essay. Hard to follow at times but interesting arguments and I like the pictures 👍
Profile Image for Lee Barry.
Author 17 books14 followers
December 12, 2019
I loved Visual Intelligence. I don’t know what happened with this one. I did like the chapter on polychromy and made the book useful. He goes into synesthesia, but that’s already well-covered.

Essentially, what he seems to be saying is that all perception is a matter of "habit"--a "System 1" response, to our detriment. In any case, who really knows what he’s getting at? What is the benefit (for our fitness) if we can’t apply it to knowing whether we need to do anything about climate change, for example? Or can we?

The complexity of this surely can be simplified from other perspectives, and consequently be more useful.
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