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The fringe of physics is not a sharp boundary with truth on one side and fantasy on the other. All of science is uncertain and subject to revision. The glory of science is to imagine more than we can prove. The fringe is the unexplored territory where truth and fantasy are not yet disentangled.

So long as we don’t think that the physicists’ space is more fundamental than, or is the ultimate reality of, lived space, then no harm is done.

in contemporary physics, space is curved, or non-Euclidean. In non-Euclidean space, the sum of the angles of a triangle may be greater than 180°; more importantly, the shortest distance between two points may not be a straight line, but a curved one.

When we first hear talk of ‘curved space’ we rebel. The least we should ask of something said to be curved is that it should have edges, surfaces, and parts that look or feel curved, which space itself does not. Analogies are offered to make the idea less counter-intuitive

Physicists will smile at taking the analogy too literally. But if it is not taken literally, it lacks explanatory force. And taken literally, it is seriously misleading. The curvature of an object such as the earth is extrinsic – evident in its surface

From Pythagoras onwards we have been prone to the illusion that our ways of geometrising space capture space itself – perhaps even believing that the mathematical logic of pure quantities is somehow ‘out there’. However, the immense power of mathematical physics – which requires abstracting from phenomenal reality and the reduction of experienced and experienceable reality to mere parameters to which numerical values are assigned – does not justify uncritically accepting concepts such as ‘curved space’ that attempt to re-insert phenomenal appearances into its abstractions. On the contrary, we should acknowledge that ‘unreasonably effective’ mathematics (to borrow Eugene Wigner’s phrase) can take us to places to which nothing non-mathematical corresponds. For instance, consider the assumption, central to modern cosmology, that space itself is expanding.

If we’re going to try to understand human behavior and use this knowledge to design the world around us—including institutions such as taxes, education systems, and financial markets—we need to use additional tools and other disciplines, including psychology, sociology, and philosophy. Rational economics is useful, but it offers just one type of input

But the impacts of learning on one of the most primal portions of the brain have been surprisingly underappreciated, both scientifically and outside the lab. Most of us pay little attention to our motor cortex, which controls how well we can move.

We like watching athletes in action, he said. But most of us make little effort to hone our motor skills in adulthood, and very few of us try to expand them by, for instance, learning a new sport. We could be short-changing our brains. Past neurological studies in people have shown that learning a new physical skill in adulthood, such as juggling, leads to increases in the volume of gray matter in parts of the brain related to movement control.

Even more compelling, a 2014 study with mice found that when the mice were introduced to a complicated type of running wheel, in which the rungs were irregularly spaced so that the animals had to learn a new, stutter-step type of running, their brains changed significantly. Learning to use these new wheels led to increased myelination of neurons in the animals’ motor cortexes. Myelination is the process by which parts of a brain cell are insulated, so that the messages between neurons can proceed more quickly and smoothly.

Scientists once believed that myelination in the brain occurs almost exclusively during infancy and childhood and then slows or halts altogether. But the animals running on the oddball wheels showed notable increases in the myelination of the neurons in their motor cortex even though they were adults.

In other words, learning the new skill had changed the inner workings of the adult animals’ motor cortexes; practicing a well-mastered one had not. “We don’t know” whether comparable changes occur within the brains of grown people who take up a new sport or physical skill, Dr. Krakauer said. But it seems likely, he said. “Motor skills are as cognitively challenging” in their way as traditional brainteasers such as crossword puzzles or brain-training games, he said. So adding a new sport to your repertory should have salutary effects on your brain, and also, unlike computer-based games, provide all the physical benefits of exercise.

noting that the history of particle physics is rife with statistical flukes and anomalies that disappeared when more data was compiled

A coincidence is the most probable explanation for the surprising bumps in data from the collider, physicists from the experiments cautioned

Physicists could not help wondering if history was about to repeat itself. It was four years ago this week that the same two teams’ detection of matching bumps in Large Hadron Collider data set the clock ticking for the discovery of the Higgs boson six months later.

If the particle is real, Dr. Lykken said, physicists should know by this summer, when they will have 10 times as much data to present to scientists from around the world who will convene in Chicago

The Higgs boson was the last missing piece of the Standard Model, which explains all we know about subatomic particles and forces. But there are questions this model does not answer, such as what happens at the bottom of a black hole, the identity of the dark matter and dark energy that rule the cosmos, or why the universe is matter and not antimatter.

CERN physicists have been running their collider at nearly twice the energy with which they discovered the Higgs, firing twin beams of protons with 6.5 trillion electron volts of energy at each other in search of new particles to help point them to deeper laws.The main news since then has been mainly that there is no news yet, only tantalizing hints, bumps in the data, that might be new particles and signposts of new theories, or statistical demons.

Or it could be a more massive particle that has decayed in steps down to a pair of photons. Nobody knows. No model predicted this, which is how some scientists like it.

“The more nonstandard the better,” said Joe Lykken, the director of research at the Fermi National Accelerator Laboratory and a member of one of the CERN teams. “It will give people a lot to think about. We get paid to speculate.”

When physicists announced in 2012 that they had indeed discovered the Higgs boson, it was not the end of physics. It was not even, to paraphrase Winston Churchill, the beginning of the end.It might, they hoped, be the end of the beginning.

Such a discovery would augur a fruitful future for cosmological wanderings and for the CERN collider, which will be running for the next 20 years.

Is nature really this weird? Or is this apparent weirdness just a reflection of our imperfect knowledge of nature?

The answer depends on how you interpret the equations of quantum mechanics, the mathematical theory that has been developed to describe the interactions of elementary particles. The success of this theory is unparalleled: Its predictions, no matter how “spooky,” have been observed and verified with stunning precision. It has also been the basis of remarkable technological advances. So it is a powerful tool. But is it also a picture of reality?

Does the wave function directly correspond to an objective, observer-independent physical reality, or does it simply represent an observer’s partial knowledge of it?

If there is an objective reality at all, the paper demonstrates, then the wave function is in fact reality-based.

What this research implies is that we are not just hearing different “stories” about the electron, one of which may be true. Rather, there is one true story, but it has many facets, seemingly in contradiction, just like in “Rashomon.” There is really no escape from the mysterious — some might say, mystical — nature of the quantum world.

We should be careful to recognize that the weirdness of the quantum world does not directly imply the same kind of weirdness in the world of everyday experience.

This is why, in fact, we are able to describe the objects around us in the language of classical physics.

I suggest that we regard the paradoxes of quantum physics as a metaphor for the unknown infinite possibilities of our own existence.

There are two problems. One is that quantum mechanics, as it is enshrined in textbooks, seems to require separate rules for how quantum objects behave when we’re not looking at them, and how they behave when they are being observed

Why are observations special? What counts as an “observation,” anyway? When exactly does it happen? Does it need to be performed by a person? Is consciousness somehow involved in the basic rules of reality?

Together these questions are known as the “measurement problem” of quantum theory.

The other problem is that we don’t agree on what it is that quantum theory actually describes, even when we’re not performing measurements.

We describe a quantum object such as an electron in terms of a “wave function,” which collects the superposition of all the possible measurement outcomes into a single mathematical object

But what is the wave function? Is it a complete and comprehensive representation of the world? Or do we need additional physical quantities to fully capture reality, as Albert Einstein and others suspected? Or does the wave function have no direct connection with reality at all, merely characterizing our personal ignorance about what we will eventually measure in our experiments?

For years, the leading journal in physics had an explicit policy that papers on the foundations of quantum mechanics were to be rejected out of hand

Many biological ideas proposed during the past 150 years stood in stark conflict with what everybody assumed to be true. The acceptance of these ideas required an ideological revolution. And no biologist has been responsible for more—and for more drastic—modifications of the average person’s worldview than Charles Darwin

. Evolutionary biology, in contrast with physics and chemistry, is a historical science—the evolutionist attempts to explain events and processes that have already taken place. Laws and experiments are inappropriate techniques for the explication of such events and processes. Instead one constructs a historical narrative, consisting of a tentative reconstruction of the particular scenario that led to the events one is trying to explain.

The discovery of natural selection, by Darwin and Alfred Russel Wallace, must itself be counted as an extraordinary philosophical advance

The concept of natural selection had remarkable power for explaining directional and adaptive changes. Its nature is simplicity itself. It is not a force like the forces described in the laws of physics; its mechanism is simply the elimination of inferior individuals

A diverse population is a necessity for the proper working of natural selection

Because of the importance of variation, natural selection should be considered a two-step process: the production of abundant variation is followed by the elimination of inferior individuals

By adopting natural selection, Darwin settled the several-thousandyear- old argument among philosophers over chance or necessity. Change on the earth is the result of both, the first step being dominated by randomness, the second by necessity

Another aspect of the new philosophy of biology concerns the role of laws. Laws give way to concepts in Darwinism. In the physical sciences, as a rule, theories are based on laws; for example, the laws of motion led to the theory of gravitation. In evolutionary biology, however, theories are largely based on concepts such as competition, female choice, selection, succession and dominance. These biological concepts, and the theories based on them, cannot be reduced to the laws and theories of the physical sciences

Despite the initial resistance by physicists and philosophers, the role of contingency and chance in natural processes is now almost universally acknowledged. Many biologists and philosophers deny the existence of universal laws in biology and suggest that all regularities be stated in probabilistic terms, as nearly all so-called biological laws have exceptions. Philosopher of science Karl Popper’s famous test of falsification therefore cannot be applied in these cases.

To borrow Darwin’s phrase, there is grandeur in this view of life. New modes of thinking have been, and are being, evolved. Almost every component in modern man’s belief system is somehow affected by Darwinian principles

that not only the cerebral cortex, but the entire auditory pathway, represents sounds according to prior expectations.

Although participants recognised the deviant faster when it was placed on positions where they expected it, the subcortical nuclei encoded the sounds only when they were placed in unexpected positions.

Predictive coding assumes that the brain is constantly generating predictions about how the physical world will look, sound, feel, and smell like in the next instant, and that neurons in charge of processing our senses save resources by representing only the differences between these predictions and the actual physical world.

e have now shown that this process also dominates the most primitive and evolutionary conserved parts of the brain. All that we perceive might be deeply contaminated by our subjective beliefs on the physical world."

Developmental dyslexia, the most wide-spread learning disorder, has already been linked to altered responses in subcortical auditory pathway and to difficulties on exploiting stimulus regularities in auditory perception.

“Big parts of our brains are devoted to making sense of touch and our skin has billions of cells that process information about it,”

“The right type of friendly touch—like hugging your partner or linking arms with a dear friend—calms your stress response down. [Positive] touch activates a big bundle of nerves in your body that improves your immune system, regulates digestion and helps you sleep well. It also activates parts of your brain that help you empathize.”

Psychologist Sheldon Cohen and other researchers at Carnegie Mellon University cited hugging specifically as a form of touch that can strengthen the immune system in a 2014 study investigating whether receiving hugs—and more broadly, social support that gives the perception that one is cared for—could make people less susceptible to one of the viruses that causes the common cold.

Broadly speaking, the participants who had reported having more social support were less likely to get sick—and those who got more hugs were far more likely to report feeling socially supported.

Everybody should be open to people being a little more socially distant and not touching as much. Some of it will return and some of it won’t.”

Although there’s no exact substitute for human touch, if you’re struggling with this aspect of self-isolating in particular, there are a few alternatives that can offer similar health benefits for people who are social distancing

“When we’re touched [in a positive way], a cascade of events happens in the brain and one of the important ones is the release of a neurochemical called oxytocin,”

Keltner adds that dancing, singing or doing yoga with others via an online platform can also be highly effective substitutes for physical contact

“Not only would it be good to prevent coronavirus disease; it probably would decrease instances of influenza dramatically in this country,”

Zak says U.S. customs like shaking hands and hugging may be changed forever and suggests that non-tactile greetings like a nod, bow or wave may come to replace them. However, he says it will still be important to find ways to reintroduce the humanity of positive touch into in-person interactions without putting anyone’s physical or mental health in jeopardy.

“In-person interactions have a big effect on the brain releasing oxytocin, but interacting via video is actually not that [different],” he explains. “It’s maybe 80% as effective. Video conferencing is a great way to see and be seen.”

But for those who are quarantining alone or with people with whom they don’t have physical contact, loneliness and social isolation are growing health concerns.

this process reduces stress and improves immunity. “That’s super valuable in a time of pandemic.”

If you’re using a video chat service for work or school, Zak recommends that you take five minutes at the beginning of the call to focus on interpersonal connection.

to illustrate how dance parties like Daybreaker can be beneficial for people’s physical and mental health. “When you create a dance experience driven by music, community and participation, that’s how you’re able to release all four happy brain chemicals,” Agrawal says.

this distinction between mental and physical is not meaningful. Anxiety does not cause stomach aches; rather, feelings of anxiety and stomach aches are both ways that human brains make sense of physical discomfort

There is no such thing as a purely mental cause, because every mental experience has roots in the physical budgeting of your body. This is one reason physical actions like taking a deep breath, or getting more sleep, can be surprisingly helpful in addressing problems we traditionally view as psychological.

Your burden may feel lighter if you understand your discomfort as something physical. When an unpleasant thought pops into your head, like “I can’t take this craziness anymore,” ask yourself body-budgeting questions. “Did I get enough sleep last night? Am I dehydrated? Should I take a walk? Call a friend? Because I could use a deposit or two in my body budget.”

I’m not saying you can snap your fingers and dissolve deep misery, or sweep away depression with a change of perspective. I’m suggesting that it’s possible to acknowledge what your brain is actually doing and take some comfort from it

Your brain is not for thinking. Everything that it conjures, from thoughts to emotions to dreams, is in the service of body budgeting. This perspective, adopted judiciously, can be a source of resilience in challenging times.

In 1972, using duct tape and spare parts in the basement on the campus of the University of California, Berkeley, Dr. Clauser and a graduate student, Stuart Freedman, who died in 2012, endeavored to perform Bell’s experiment to measure quantum entanglement. In a series of experiments, he fired thousands of light particles, or photons, in opposite directions to measure a property known as polarization, which could have only two values — up or down. The result for each detector was always a series of seemingly random ups and downs. But when the two detectors’ results were compared, the ups and downs matched in ways that neither “classical physics” nor Einstein’s laws could explain. Something weird was afoot in the universe. Entanglement seemed to be real.

in 2002, Dr. Clauser admitted that he himself had expected quantum mechanics to be wrong and Einstein to be right. “Obviously, we got the ‘wrong’ result. I had no choice but to report what we saw, you know, ‘Here’s the result.’ But it contradicts what I believed in my gut has to be true.” He added, “I hoped we would overthrow quantum mechanics. Everyone else thought, ‘John, you’re totally nuts.’”

the correlations only showed up after the measurements of the individual particles, when the physicists compared their results after the fact. Entanglement seemed real, but it could not be used to communicate information faster than the speed of light.

In 1982, Dr. Aspect and his team at the University of Paris tried to outfox Dr. Clauser’s loophole by switching the direction along which the photons’ polarizations were measured every 10 nanoseconds, while the photons were already in the air and too fast for them to communicate with each other. He too, was expecting Einstein to be right.

Quantum predictions held true, but there were still more possible loopholes in the Bell experiment that Dr. Clauser had identified

For example, the polarization directions in Dr. Aspect’s experiment had been changed in a regular and thus theoretically predictable fashion that could be sensed by the photons or detectors.

Anton Zeilinger

added even more randomness to the Bell experiment, using random number generators to change the direction of the polarization measurements while the entangled particles were in flight.

Once again, quantum mechanics beat Einstein by an overwhelming margin, closing the “locality” loophole.

as scientists have done more experiments with entangled particles, entanglement is accepted as one of main features of quantum mechanics and is being put to work in cryptology, quantum computing and an upcoming “quantum internet

One of its first successes in cryptology is messages sent using entangled pairs, which can send cryptographic keys in a secure manner — any eavesdropping will destroy the entanglement, alerting the receiver that something is wrong.

, with quantum mechanics, just because we can use it, doesn’t mean our ape brains understand it. The pioneering quantum physicist Niels Bohr once said that anyone who didn’t think quantum mechanics was outrageous hadn’t understood what was being said.

In his interview with A.I.P., Dr. Clauser said, “I confess even to this day that I still don’t understand quantum mechanics, and I’m not even sure I really know how to use it all that well. And a lot of this has to do with the fact that I still don’t understand it.”

The particle that carries his name is perhaps the single most stunning example of how seemingly abstract mathematical ideas can make predictions which turn out to have huge physical consequences.”

The Royal Swedish Academy of Sciences, which awards the Nobel, said at the time the standard model of physics which underpins the scientific understanding of the universe “rests on the existence of a special kind of particle: the Higgs particle. This particle originates from an invisible field that fills up all space.“Even when the universe seems empty this field is there. Without it, we would not exist, because it is from contact with the field that particles acquire mass. The theory proposed by Englert and Higgs describes this process.”

Even before the evolution of a central brain, nervous systems took advantage of a simple computing trick: competition.

It coordinates something called overt attention – aiming the satellite dishes of the eyes, ears, and nose toward anything important.

Selective enhancement therefore probably evolved sometime between hydras and arthropods—between about 700 and 600 million years ago, close to the beginning of complex, multicellular life

The next evolutionary advance was a centralized controller for attention that could coordinate among all senses. In many animals, that central controller is a brain area called the tectum

At any moment only a few neurons win that intense competition, their signals rising up above the noise and impacting the animal’s behavior. This process is called selective signal enhancement, and without it, a nervous system can do almost nothing.

All vertebrates—fish, reptiles, birds, and mammals—have a tectum. Even lampreys have one, and they appeared so early in evolution that they don’t even have a lower jaw. But as far as anyone knows, the tectum is absent from all invertebrates

According to fossil and genetic evidence, vertebrates evolved around 520 million years ago. The tectum and the central control of attention probably evolved around then, during the so-called Cambrian Explosion when vertebrates were tiny wriggling creatures competing with a vast range of invertebrates in the sea.

The tectum is a beautiful piece of engineering. To control the head and the eyes efficiently, it constructs something called an internal model, a feature well known to engineers. An internal model is a simulation that keeps track of whatever is being controlled and allows for predictions and planning.

The tectum’s internal model is a set of information encoded in the complex pattern of activity of the neurons. That information simulates the current state of the eyes, head, and other major body parts, making predictions about how these body parts will move next and about the consequences of their movement

In fish and amphibians, the tectum is the pinnacle of sophistication and the largest part of the brain. A frog has a pretty good simulation of itself.

With the evolution of reptiles around 350 to 300 million years ago, a new brain structure began to emerge – the wulst. Birds inherited a wulst from their reptile ancestors. Mammals did too, but our version is usually called the cerebral cortex and has expanded enormously

The cortex also takes in sensory signals and coordinates movement, but it has a more flexible repertoire. Depending on context, you might look toward, look away, make a sound, do a dance, or simply store the sensory event in memory in case the information is useful for the future.

The most important difference between the cortex and the tectum may be the kind of attention they control. The tectum is the master of overt attention—pointing the sensory apparatus toward anything important. The cortex ups the ante with something called covert attention. You don’t need to look directly at something to covertly attend to it. Even if you’ve turned your back on an object, your cortex can still focus its processing resources on it

The cortex needs to control that virtual movement, and therefore like any efficient controller it needs an internal model. Unlike the tectum, which models concrete objects like the eyes and the head, the cortex must model something much more abstract. According to the AST, it does so by constructing an attention schema—a constantly updated set of information that describes what covert attention is doing moment-by-moment and what its consequences are

Covert attention isn’t intangible. It has a physical basis, but that physical basis lies in the microscopic details of neurons, synapses, and signals. The brain has no need to know those details. The attention schema is therefore strategically vague. It depicts covert attention in a physically incoherent way, as a non-physical essence

this, according to the theory, is the origin of consciousness. We say we have consciousness because deep in the brain, something quite primitive is computing that semi-magical self-description.

I’m reminded of Teddy Roosevelt’s famous quote, “Do what you can with what you have where you are.” Evolution is the master of that kind of opportunism. Fins become feet. Gill arches become jaws. And self-models become models of others. In the AST, the attention schema first evolved as a model of one’s own covert attention. But once the basic mechanism was in place, according to the theory, it was further adapted to model the attentional states of others, to allow for social prediction. Not only could the brain attribute consciousness to itself, it began to attribute consciousness to others.

In the AST’s evolutionary story, social cognition begins to ramp up shortly after the reptilian wulst evolved. Crocodiles may not be the most socially complex creatures on earth, but they live in large communities, care for their young, and can make loyal if somewhat dangerous pets.

If AST is correct, 300 million years of reptilian, avian, and mammalian evolution have allowed the self-model and the social model to evolve in tandem, each influencing the other. We understand other people by projecting ourselves onto them. But we also understand ourselves by considering the way other people might see us.

t the cortical networks in the human brain that allow us to attribute consciousness to others overlap extensively with the networks that construct our own sense of consciousness.

Language is perhaps the most recent big leap in the evolution of consciousness. Nobody knows when human language first evolved. Certainly we had it by 70 thousand years ago when people began to disperse around the world, since all dispersed groups have a sophisticated language. The relationship between language and consciousness is often debated, but we can be sure of at least this much: once we developed language, we could talk about consciousness and compare notes

Maybe partly because of language and culture, humans have a hair-trigger tendency to attribute consciousness to everything around us. We attribute consciousness to characters in a story, puppets and dolls, storms, rivers, empty spaces, ghosts and gods. Justin Barrett called it the Hyperactive Agency Detection Device, or HADD

the HADD goes way beyond detecting predators. It’s a consequence of our hyper-social nature. Evolution turned up the amplitude on our tendency to model others and now we’re supremely attuned to each other’s mind states. It gives us our adaptive edge. The inevitable side effect is the detection of false positives, or ghosts.

Worse still, the laws of physics themselves seem to be working against us. Ours isn’t just a randomly hostile universe, it's an actively hostile universe

The history of physics, in fact, is a marvel of using simple symmetry principles to construct complicated laws of the universe

if the entire universe were made symmetric, then all of the good features (e.g., you) are decidedly asymmetric lumps that ruin the otherwise perfect beauty of the cosmo

it would be a mistake to be comforted by the symmetries of the universe. In truth, they are your worst enemies. Everything we know about those rational, predictable arrangements dictates that you shouldn't be here at all.

How hostile is the universe to your fundamental existence? Very. Even the simplest assumptions about our place in the universe seem to lead inexorably to devastating results

The symmetry of the universe would bake us in no time at all, but an asymmetry rescues us

In literally every experiment and observation that we’ve ever done, matter and antimatter get created (or annihilated) in perfect concert. That is, every experiment except for one: us.

Matter and antimatter should have completely annihilated one another in the first nanoseconds after the Big Bang. You should not even exist. But you do, and there’s lots more matter where you came from.

if the perfect symmetry between matter and antimatter remained perfect, you wouldn’t be here to think about it.

The flow of time (as near as we can tell) is completely arbitrary. Does entropy increase with time or does it make time? Are our memories the thing that ultimately breaks the symmetry of time?

It seems only a matter of luck (and some fairly arbitrary-looking math) that a symmetric universe would end up being remotely hospitable to complex creatures like us

Without electrons binding to protons, there would be no chemistry, no molecules, and nothing more complicated than a cloud of charged gas. And you’re not a sentient cloud of gas, are you?

materialism is not the greedy desire for material goods, but rather the belief that the fundamental reality of the world is material;

idealism is not the aspiration toward lofty and laudable goals, but rather the belief that the fundamental reality of the world is mental or idea-like. English-speaking philosophers today tend to speak of “physicalism” or “naturalism” rather than materialism (perhaps to avoid confusion with the Wall Street sense of the term). At the same time, Anglo-American historians of philosophy continue to find the distinction between materialism and idealism a useful one in our attempts at categorizing past schools of thought. Democritus and La Mettrie were materialists; Hobbes was pretty close. Berkeley and Kant were idealists; Leibniz may have been.

And it was these paradoxes that led the Irish philosopher to conclude that talk of matter was but a case of multiplying entities beyond necessity. For Berkeley, all we can know are ideas, and for this reason it made sense to suppose that the world itself consists in ideas.

Soviet and Western Marxists alike, by stark contrast, and before them the French “vulgar” (i.e., non-dialectical) materialists of the 18th century, saw and see the material world as the base and cause of all mental activity, as both bringing ideas into existence, and also determining the form and character of a society’s ideas in accordance with the state of its technology, its methods of resource extraction and its organization of labor. So here to focus on the material is not to become distracted from the true source of being, but rather to zero right in on it.

one great problem with the concept of materialism is that it says very little in itself. What is required in addition is an elaboration of what a given thinker takes matter, or ideas, to be. It may not be just the Marxist aftertaste, but also the fact that the old common-sense idea about matter as brute, given stuff has turned out to have so little to do with the way the physical world actually is, that has led Anglo-American philosophers to prefer to associate themselves with the “physical” or the “natural” rather than with the material.  Reality, they want to say, is just what is natural, while everything else is in turn “supernatural” (this distinction has its clarity going for it, but it also seems uncomfortably close to tautology). Not every philosopher has a solid grasp of subatomic physics, but most know enough to grasp that, even if reality is eventually exhaustively accounted for through an enumeration of the kinds of particles and a few basic forces, this reality will still look nothing like what your average person-in-the-street takes reality to be.

The 18th-century idealist philosopher George Berkeley strongly believed that matter was only a fiction contrived by philosophers in the first place, for which the real people had no need. For Berkeley, there was never anything common-sensical about matter. We did not need to arrive at the era of atom-splitting and wave-particle duality, then, in order for the paradoxes inherent in matter to make themselves known (is it infinitely divisible or isn’t it?

Central to this performance was the concept of  “materialism.” The entire history of philosophy, in fact, was portrayed in Soviet historiography as a series of matches between the materialist home-team and its “idealist” opponents, beginning roughly with Democritus (good) and Plato (bad), and culminating in the opposition between official party philosophy and logical positivism, the latter of which was portrayed as a shrouded variety of idealism. Thus from the “Short Philosophical Dictionary,” published in Moscow in 1951, we learn that the school of logical empiricism represented by Rudolf Carnap, Otto Neurath and others, “is a form of subjective idealism, characteristic of degenerating bourgeois philosophy in the epoch of the decline of capitalism.”Now the Soviet usage of this pair of terms appears to fly in the face of our ordinary, non-philosophical understanding of them (that, for example,  Wall Street values are “materialist,” while the Occupy movement is “idealist”). One might have thought that the communists should be flinging the “materialist” label at their capitalist enemies, rather than claiming it for themselves. One might also have thought that the Bolshevik Revolution and the subsequent failed project of building a workers’ utopia was nothing if not idealistic.

Consider money. Though it might sometimes be represented by bank notes or coins, money is an immaterial thing par excellence, and to seek to acquire it is to move on the plane of ideas. Of course, money can also be converted into material things, yet it seems simplistic to suppose that we want money only in order to convert it into the material things we really want, since even these material things aren’t just material either: they are symbolically dense artifacts, and they convey to others certain ideas about their owners. This, principally, is why their owners want them, which is to say that materialists (in the everyday sense) are trading in ideas just as much as anyone else.

In the end no one really cares about stuff itself. Material acquisitions — even, or perhaps especially, material acquisitions of things like Rolls Royces and Rolexes — are maneuvers within a universe of materially instantiated ideas. This is human reality, and it is within this reality that mystics, scientists, and philosophers alike are constrained to pursue their various ends, no matter what they might take the ultimate nature of the external world to be.