UC Irvine cognitive scientist Donald Hoffman recently explored this issue in his discussion of his 2019 book, The Case Against Reality: Why Evolution Hid the Truth from Our Eyes. Hoffman explains that, contrary to popular belief, perceiving the world accurately does not give organisms a survival advantage. It seems intuitively obvious that animals who see reality as it is would be better at finding food, avoiding predators, and seeking mates — but what really matters is adaptive behavior tuned to fitness payoffs. Hoffman and his mathematician colleague, Chetan Prakash, have constructed a “Fitness-Beats-Truth Theorem” that they have tested and confirmed in multiple computer simulations. Their research has been peer-reviewed and published in academic journals. Hoffman and Prakash stress that the structures of fitness payoffs differ from the structures of objective reality. As Hoffman says, “What we normally take to be reality is, in fact, a simplified virtual reality, shaped by natural selection to guide adaptive action.” According to his interface theory of perception, each perceptual system is a user interface analogous to the desktop screen of a laptop. The icons on the desktop hide reality but deliver functionality.
Hoffman claims that evolution hid the truth from us. Westerhoff goes one step further and makes the more radical assertion that the real world does not even exist. Westerhoff’s important qualification, however, is that, by “real,” he means independent of human “cognitive activities.” Since everything we believe and experience can be considered a product of cognitive activity, mind-independent reality is unknowable, and Westerhoff’s claim appears more plausible. He acknowledges that the brain creates a representation of external objects, but “nevertheless, this representation does not have any implications for existence beyond the representational framework.” This represented world is “built around a conceptual scaffold of notions like causation, time, space, logical implication, physical, mental, abstract, concrete, and so forth.” The point is that the representation and that which it represents are two different things. For example, the objects in a dream do not have an existence outside the dream. In a dream, the brain can generate our experience of an object (presumably via a storage retrieval process) without the presence of the object. We create the representation, but we do not have direct contact with the thing represented. Ordinary daytime experiences can be thought of as dreams constrained by sensory data. In both the dreaming and waking states, our brains create a virtual reality so automatically and so perfectly that we take it to be the real thing. We are totally unaware of this ongoing reality-construction process, which is invisible to us.
Lucid dreams offer insights into the Hoffman/Westerhoff realm of virtual worlds. In such a dream we are simultaneously dreaming and aware that we are so doing. In addition, we may be able to control the dream narrative and its contents. We say to ourselves in the midst of a lucid dream, “I know this is a dream, but I am in control.” This experience is instructive because it enables us to see ourselves as the creators of a virtual reality while we are dreaming. In a lucid dream, we get a glimpse of the normally invisible virtual-reality construction process.
Both Hoffman and Westerhoff agree that the apparent structure of reality experienced by an organism is simply the structure that facilitates its survival. The organism’s picture of the world is not a mirror of the basic structures of the things in themselves, but a custom-made stage set aimed at promoting survival-enhancing behavior. The neural circuitry of living things evolved to promote the survival and reproduction of that organism. Nervous systems are exquisitely adapted to the ecological niche of each species. Therefore, what each organism regards as “real” depends on its nervous system. For example, the retinal light receptors of different organisms respond to different portions of the electromagnetic spectrum. Honeybees respond to ultraviolet wavelengths that human eyes can’t detect, and rattlesnakes are sensitive to infrared radiation we can’t perceive. There are numerous other examples of species-specific environmental inputs: electrical fields for eels, air compression waves for echolocating bats, and so on. And, of course, the smelling and hearing capabilities of our canine pets far exceed our own capabilities. The point is that what is perceived as real for one organism is not perceived as real for another. It is the neural circuitry of the animal that constructs a virtual world out of its environmental input.
The phenomenon of synesthesia, experienced by about one percent of the population, further underscores the role of the brain in constructing virtual realities. Normally, incoming sensory data are transduced into electrochemical patterns in the brain. The signals from each sensory organ are processed in different regions of the cerebral cortex. For example, the visual cortex, located at the back of the brain, processes vision. In individuals with synesthesia, microscopic changes in brain wiring cause inputs geared for one sensory system of the brain to be transferred to another. For the most part, synesthetes experience sensory inputs the way the rest of us do but, in addition, may also hear colors, taste sounds, feel odors, or smell textures. In other words, what is perceived as reality depends on how the brain processes incoming sensory data. My reality is not your reality. Thus, perceiver variability both across and within species makes it impossible to provide a true and complete description of the way the world is. We get the unmistakable impression that the qualities of the external world inhere in the world itself, not recognizing that its phenomenal qualities represent the interface between our senses and an unknown reality.
Like Hoffman, Westerhoff maintains that we live in a virtual world akin to a computer simulation generated by our brains. The model of the world that the brain produces is perceived as if it is external and perception-independent, even though it is neither. Self-referentially, this model includes the perceiver as part of the simulation. The self itself is a perception! Cognitive scientist Douglas Hofstadter makes a similar argument in his appropriately titled 2007 book I Am a Strange Loop. According to both Westerhoff and Hofstadter, the brain constructs images of the self and the external world that connect in a mutually reinforcing feedback loop. Of course, this neuronal construction process is invisible to us, and we only experience the “self-in-the-world” end result. But both the perceiving self “in here” and the perceived world “out there” are mirages. As Westerhoff puts it, “The simulated self inhabits a simulated world.”
What is this simulated world we inhabit a simulation of? It cannot be a faithful simulation of the real world because we do not know what the real world is and have not even established that it exists. But we see and feel solid stuff that takes up space all around us, so what is going on? Cognitive scientist Hoffman and philosopher Westerhoff answer this question differently. According to Hoffman, “Something is there in objective reality,” but “that reality is utterly unlike our perception of objects in space and time” and “is almost surely not DNA, RNA, chromosomes, organisms, or resources.” Westerhoff puts it this way: “We cannot escape the virtual world generated by the brain because there would be no ‘we’ outside the simulation.” For Westerhoff, any claim of existence outside the simulation is itself part of the simulation. We are stuck in the simulation, and all statements about matter need to be understood as statements about mental stuff appearing as matter.
Westerhoff’s conception thus bears some resemblance to Berkeleyan idealism, which regards all external objects as mental entities existing in the mind of God. There are also parallels to Kant’s noumenal/phenomenal distinction, which differentiates the unknowable noumena, or “things in themselves,” from phenomena, or “things as they appear.” For Westerhoff, however, neither the mind of God nor noumena exist. On the other hand, Hoffman’s objective reality, which is outside space and time, might certainly be considered noumenal in a Kantian sense.
According to Westerhoff, if there is no real world, and therefore no rock-bottom reality, it follows that there can be no fundamental truths. Any assertion of an allegedly true fact would have to depend on another fact, leading either to an infinite regress with no ultimate grounding or to a circular chain of reasoning that closes back on itself in a never-ending loop. Either way, we never reach a foundational truth — there is just a chain of dependent relationships.
Westerhoff therefore proposes a coherence theory of truth, in which a set of statements acquire their truth by their coherence with each other, not by virtue of their direct contact with a real world or their dependence on an ultimate underlying truth. Within this conceptual framework, there is a form of circularity, but it is a logical circularity in the absence of a base reality. The reality of our experience is a relational reality in which the properties of the world stem from the relations between the objects in it. There is no context-independent notion of truth, and there are no foundational truths on which other truths depend. The coherence theory of truth is nonhierarchical — all truths are essentially on the same level.
Westerhoff’s thesis is well-reasoned and intellectually, albeit not emotionally, persuasive. Caught up in the melodrama of our everyday lives, we probably cannot give up our deep-rooted intuition of a what-you-see-is-what-you-get world, but perhaps we can at least begin to question it.
It is noteworthy that Westerhoff’s subspecialty is ancient Indian philosophy. In his preface, however, he states that he has scrupulously avoided any references to ancient Indian philosophy because he wants his arguments to stand on their own. Nevertheless, the theme of this book might best be summed up in the words of Nāgārjuna, the second-century founder of the Mādhyamika school of Mahāyāna Buddhism: “All things should be regarded as in a dream.”
David Voron is a Clinical Professor Emeritus at the Keck University of Southern California School of Medicine. He has contributed to Skeptic magazine, e-Skeptic, The Secular Web, and Internet Infidels.