Friday, July 12, 2013

Book: "The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality"

Where did the big bang happen? It happened everywhere.*
A trip around big ideas in physics and the cosmological rules (re: the symmetries) that govern our universe, The Universe in the Rearview Mirror: How Hidden Symmetries Shape Reality is an easy read covering some less easy theoretical concepts. Relativity (general and special), sub-atomic particle physics, the directionality of time itself, all are among the topics illustrated by author Dave Goldberg. Goldberg, an astrophysicist by trade and frequently asked physicist on, skillfully delivers conceptually dense material with levity, in a familiar format well suited for the general scientifically-minded readership, and with an often tongue-in-cheek style much like I imagine he employs when teaching his undergraduates at Drexel University.

Like any good survey of a scientific field, The Universe in the Rearview Mirror** is salted liberally with quotes from historically influential figures. One that Goldberg utilizes in his introduction as a succinct justification of the book's premise comes from Nobel laureate Phil Anderson:
"It is only slightly overstating the case to say that physics is the study of symmetry."
And from there each chapter of the book gives a progressively compelling case for why such a statement, characterizing physics as the study of symmetry, is indeed only slightly overstating the case. Building from the more intuitive forms of symmetry (e.g. the symmetry of a [rearview] mirror; CPT symmetry; Lorentz invariance) up through mind-bending internal symmetries, critical at the most fundamental levels of physics, and ultimately on to how the breaking of certain symmetries is the crucial factor to the universe we see around us, The Universe in the Rearview Mirror orders the daunting complexities of modern theoretical physics into elegant underlying symmetries, allowing the rest of us to make some sense of it, even if only a little bit.

Of course the symmetries don't explain everything. But they aren't supposed to either. In fact much of the book has author Dave Goldberg pointing out just how wrong we often are when it comes to understanding this material intuitively. The theme of symmetries gives us a model with which to gain a better working understanding of the universe. And yet, in the end what we have is still a model and not the universe. Werner Heisenberg said it best:
"We have to remember that what we observe is not nature herself, but nature exposed to our method of questioning."

The spinning disc of Antworld

*Why did the Big Bang happen everywhere? Because the universe expands like a stretching rubber sheet, not an explosion.
**While there isn't a footnote on every page, this book probably does have nearly as many footnotes as it does pages. If you don't like writing with frequent asides consider yourself warned. References to the bottom of the page aside, the notes themselves are often chuckle-worthy.

Tuesday, June 25, 2013

Review: Blindsight

Blindsight by Peter Watts

My rating: 5 of 5 stars

Suspense in the dark of space with a small cast of carefully chosen characters, driven by their thought-provoking interactions and underlying philosophical implications, and ultimately a literally maddening desire to understand that which is not like us. Makes excellent use of some fascinating concepts of real human cognitive psychology to highlight the fundamental limitations of our conscious awareness...

Now one of my favorite "hard" sci-fi books!

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Wednesday, April 25, 2012

Review: The Secret Life of Pronouns: What Our Words Say About Us

The Secret Life of Pronouns: What Our Words Say About Us
The Secret Life of Pronouns: What Our Words Say About Us by James W. Pennebaker

More interesting than just a look at pronouns grammatically, this is really a psychology book about how we put our words together (and what that can tell us), encompassing the class of "function words" (including pronouns) that make up a substantial part of our speech. Because of the role that function words play in establishing the structure we use to fill in the rest of the words we use (i.e. nouns, verbs, words with primarily semantic content), Pennebaker looks at patterns in function word frequencies and finds strong correlations with interesting real-world classifications: personality types, rhetoric, political speech, gender differences, even income and education gaps. Elucidating these various correlations forms the majority of the book.

Using function word analysis and modern Natural Language Processing techniques, Pennebaker shows how you can make predictions about the author of an anonymous text, and perform simple culturomics (e.g. gauging national "mood" after the 9/11 disaster) by surveying the text of blog posts across on the internet, all without recourse to more complex semantic information.

A recommended read for anyone interested in psychology and language, and also for those curious to see what modern technology applied to language analysis can tell us about ourselves.

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Wednesday, February 15, 2012

Review: Connectome: How the Brain's Wiring Makes Us Who We Are

Connectome: How the Brain's Wiring Makes Us Who We Are by Sebastian Seung

An accessible book to introduce and help explain the exciting theory that the mind is entirely encoded in the particular architecture of your brain. The central theme of "Connectome" is that such a mapping of the connections between neurons provides a far more complete picture of mental activity than other brain models. As Seung explains, mapping a brain's connectome would enable highly specific examination and treatment of a brain, going so far as to allow correlation of neuronal activity patterns with memory and conscious experience itself.

The catch is the monumental technical challenge of obtaining and handling so much data, as mapping a connectome, like mapping a DNA genome, is a computationally expensive process. In fact, mapping the connections in a human brain is many, many orders of magnitude more complex given the density of neurons and the intricacy of their connections in brain tissue. Furthermore, technology with the proper specificity to automate the delicate task is still in early stage development. Thus a corollary theme in the book relates to the pace of technological change: the field of connectomics banks on the continuation of exponential growth in computer processing speed (e.g. Moore's Law) and accompanying technologies. Assuming that technology continues to progress as it has, Seung proposes that connectomes will naturally become the substrate of which we discuss our mental selves and our conscious identity.

Other notes: The fundamental idea of the connectome is persuasive and fascinating, but perhaps because of such preexisting interests, this book was less in-depth than I was hoping for, and much of the content therein will be familiar to other fans of cognitive science or avid tech enthusiasts. Seung devotes the end of the book to the interesting future possibilities of cyber immortality, but they come with the usual speculation & caveats and don't yield much of a takeaway message. Seung's writing style is natural if not as crisp as a science journalist, just occasionally veering too folksy for the science (with a few awkwardly stilted metaphors).

I was originally introduced to Sebastian Seung's "Connectome" in his excellent 2010 TED Talk.

Reviews at Goodreads

Friday, October 7, 2011

The Modern Denial of Human Pacification: In Review of "The Better Angels of Our Nature"

In his lauded but controversial best-seller "The Blank Slate: The Modern Denial of Human Nature", Steven Pinker set out to quash a romanticized nostalgia for the lifestyle of people in pre-state societies: the myth of the "noble savage". The noble savage, a conception of peaceful human coexistence before civilization, emerged in part as a reaction to the philosopher Thomas Hobbes' famous suggestion that these savages indeed lived savage lives, described succinctly as "solitary, poor, nasty, brutish, and short". While Pinker doesn't write to expressly vindicate Hobbes' characterization, he does present a strong case for rejecting the overly romantic conception of pre-state peoples as non-violent noble savages, and suggests that we do ourselves a disservice in misrepresenting the history of mankind. Now, in his new book "The Better Angels of Our Nature: Why Violence Has Declined", Steven Pinker extends this rectification of prevailing but misguided opinion to grand scale, presenting a strong case for our ennobled present; we are living in the most peaceful era humanity has ever known.

Reading peacefully in the Stanford University Oval

In the famous 1969 novel "Slaughterhouse Five", Kurt Vonnegut remarks resignedly to the effect "that writing an anti-war book is like writing an anti-glacier book", a fatalistic assessment of the human condition, consigned as we are to inevitable war despite a growing wherewithal to protest it. So it goes. Well Pilgrim, Steven Pinker has good news: our novel expressions of knowledge, empathy, and reason really have turned our world away from war. Glaciers won't budge, but we have Better Angels.

Pinker blows the reader away (forgive the violent metaphor) with sheer weight of analytical shot. Slowly. At 700 pages of text interspersed with graphs and heaps of reference data, "Better Angels" is thorough-going and methodical because it has to be; contradicting common folk theories (like the noble savage), overriding an often overwhelming sense of unceasing or imminent violence from media coverage (see compassion fatigue), and compensating for a general lack of statistical thinking and probabilistic understanding in the lay public is no easy task. People are right to be skeptical of controversial theories, and knowing this Pinker has patiently lain it all out for us to see for ourselves that violence truly has declined with clear and unambiguously downward direction.

Image credit: Wall Street Journal
"Better Angels" is structured around an inventory of six Trends, five Inner Demons with four Better Angels, and five Historical Forces (Pinker can't help but enumerate). More than half of the book is dedicated to a chronological exploration of the Trends of our history, six paradigm shifts in the human condition: The Pacification Process, The Civilizing Process, The Humanitarian Revolution, The Long Peace, The New Peace, and The Rights Revolutions. The bulk of the remaining half of the text is a fascinating look at psychology and sociology, showcasing a combined total of nine human traits (the Better Angels & Inner Demons) that dictate our behavior depending on their interplay with our environment and circumstance (so intriguing that I will have to return to these explicitly in later writing). The last five items in Pinker's syllabus, the five Historical Forces, feature in the concluding chapter and encapsulate much of the book's overall content by reflecting combinations of historical trend and human trait. For this reason I will focus mostly on these five developments for this review.

The Five Major Historical Forces for Peace:
  • The Leviathan (the state; reigns in internal violence)
  • Gentle Commerce (economic incentives for cooperation)
  • Feminization (empowerment of women; men are the violent sex)
  • The Expanding Circle (empathy; sympathizing with ever wider classes)
  • The Escalator of Reason (rationality; application of empathy)

Hobbes' commentary about the always warring nature of savage man (Bellum omnium contra omnes) came in a seminal 1651 work of political theory on social contract, Leviathan. Pinker co-opts Hobbes' metaphor of the Leviathan throughout "Better Angels" to represent the state, a dispassionate central government with a monopoly on violence and the doling out of punishment. Such an authority, Hobbes argued and Pinker shows, reduces overall violence because it represents the people, the 'bystander' seeking to minimize collateral damage in any conflict between two parties under the Leviathan's umbrella ('aggressor' and 'victim'). The three roles form the corners of a "violence triangle", and an understanding of the relationships between the roles leads to an understanding of conflict, its causes, and our collective capacity to keep it in check. Knowing how to utilize the monopoly of force to control citizenry doesn't preclude a brutal autocracy from being an ultimately pacifying Leviathan for its people (any ruler can see that keeping citizens in line yields a stronger state, not to mention more tax revenue), though democracies have proven quite capable of enforcing the rule of law without resort to violent suppression as primary means. Thankfully, modern Leviathans are increasingly democratic, a trend that has continued to proliferate (e.g., the Arab Spring of this past year).

The Leviathan, referenced throughout the book as critical to the historical trends of the Pacification and Civilizing Processes, is a governmental construct that has proven to promote peace through the simple game theoretic logic of internecine deterrence. That is, minimizing conflict within the Leviathan for the greater good of the Leviathan. Pinker frames this effective deterrence in a relabeled Prisoner's Dilemma called the Pacifist's Dilemma, showing that when the Leviathan imposes penalties on conflict then the rational choice for both parties (Players A and B) shifts to pacifism (cooperation) rather than aggression (defection, which would be the go-to choice in an otherwise dangerous world, hence the dilemma).

An example of the Prisoner's Dilemma game model. Prefer a comic?

[An aside on the Prisoner's Dilemma: the always enlightening radio program Radiolab aired in their "Good Show" on the roots of altruism a fascinating segment on the Prisoner's Dilemma and human behavior, explaining the game theory behind the thought experiment by retelling a real-life World War trench scenario. They talk to mathematician Steven Strogatz and political scientist Robert Axelrod about the tit-for-tat strategies that emerge in a prolonged (repeating) dilemma. Steven Pinker touches on these Iterated Prisoner's Dilemmas explicitly in his section on revenge and he shows that the game mechanics can be seen extended in all group interaction, and is thus critical to an understanding the nature of conflict.]

Among the many rational ideals incubated by the Enlightenment that have contributed to the ongoing decline of violence, the recognition that both sides in a seemingly zero-sum game (like the Pacifist's Dilemma) can actually increase their mutual benefit by exchange (positive-sum) is among the most pacifying. Pinker, adopting Norbert Elias' descriptor "Gentle Commerce", describes this idea as often under-emphasized ("I suspect that among researchers, gentle commerce is just not a sexy idea") but nonetheless a powerful incentive for peace, citing it in his conclusion among the most meaningful historical developments alongside the Leviathan. When the economic benefits of trade increase the value of maintaining a pacifist relationship, war becomes less attractive in comparison. In the terms of the Pacifist's Dilemma, it increases the reward value of mutual cooperation for each player beyond what they might win with aggression. Exchange of specialized goods or culture never acts as a guarantor of peace alone, but rather gently encourages it like an undercurrent beneath a turbulent surface.

Feminization is the natural result of a world that has increasingly advocated equal rights for women and allowed them greater influence in the decision making process that shapes societal values, policies and norms. It is perhaps the most obvious historical force for peace; men are far more inclined to be violent than women. A little evolutionary biology can give us indications as to why the genders are not equal in their propensities. Males of the species need to compete for reproductive access to females, who have incentives for a stable family environment to raise their children (with fathers who aren't getting killed all the time). When men are in charge without input from women, their psychology of dominance contests carries over into cultures of honor where there is strong pressure to back up claims to status with violence, from the level of mano a mano duels and family blood feuds up through politics and interstate war. Women have good reasons for abjuring violence and war, psychology likewise rooted in the evolution of our species, and Pinker offers an abundance of evidence to suggest a strong link between the empowerment of women and the decline of violence.

My favorite metaphor in this study of violence is one I've often appealed to: The Expanding Circle. Another of Pinker's developmental standouts, The Expanding Circle (adapted from ethical philosopher Peter Singer's coinage) is a growing category comprising those who elicit our sympathy. Pinker explains how perspective-taking, something we do whenever we read a novel, inflates our circle of sympathetic concern. When Pinker compared the rates of literacy and long-distance idea vectors ("books") to trends in cruel treatment and homicides (related caveat: this book is chock full of grisly torture descriptions), he found that increases in literacy corresponded to the advent and perpetuation of the Humanitarian Revolution, fueling The Republic of Letters in the 17th and 18th centuries (a spiritual ancestor of our interconnected Global Village of the present day). The chronology of factors is in the right direction for a causal claim: technological advances in publishing, mass production of books, expansion of literacy, and the popularity of novels all preceded the major humanitarian reforms of the 18th century. The suddenly liberated flow of ideas, along with technologies that gave the people carrying those ideas newfound mobility (especially to move into and between cities, crucibles for progress), fostered cosmopolitan worldliness, more rapid evolution of ideas with the rise of urbanization, and critically, peace and empathy. Looking to more recent history (with the help of wonderful culture-surveying tools like the Google NGram Viewer) we can thank developments in the Expanding Circle for what Pinker calls the Rights Revolutions of the late 20th century: Civil Rights, Women's Rights, Children's Rights, Homosexual Rights, and Animal Rights. The extension of rights followed awareness of not just the range of human experience, but other sentient beings as well (in stark contrast to the utterly routine cruelty to animals during most of our coexistence). Modern sensibilities uphold the individual right to autonomy as an implicit social norm for minorities downtrodden in all but the last few decades of human society. Part of what fascinates me most about the Expanding Circle is just how rapidly it expanded in the 20th century. The idea that communication and technology work together as primary drivers of the mechanism that inflates our circle of sympathetic understanding is too enticing to ignore. Pinker expounds:

"If I were to put my money on the single most important exogenous cause of the Rights Revolutions, it would be the technologies that made ideas and people increasingly mobile. The decades of the Rights Revolutions were the decades of the electronics revolutions: television, transistor radios, cable, satellite, long-distance telephones, photocopiers, fax machines, the Internet, cell phones, text messaging, Web video. They were the decades of the interstate highway, high-speed rail, and the jet airplane. They were the decades of the unprecedented growth in higher education and in the endless frontier of scientific research. Less well known is that they were also the decades of an explosion in book publishing. From 1960 to 2000, the annual number of books published in the United States increased almost fivefold." - Steven Pinker

Closely related to The Expanding Circle and perhaps Pinker's favorite metaphor if only for the Better Angel of our nature at its core: The Escalator of Reason. The Escalator takes us step-by-step higher toward the ideal of pure objectivity, Nagel's view from nowhere, a "superrational vantage point" that through the power of reasoning allows us to consider our own interests and the interests of another as equivalent in the grand scheme of things. Our cumulative gains in reducing violence may have been impossible without faculties of reason to help us determine how and why we should encourage our Better Angels and subdue our Inner Demons. While reading I found myself thinking of reason as the 'Better Archangel' of our nature, playing a vital role in every step of moral progress we've made since its rise to ethical power in the hands of Enlightenment philosophers.

"Once a society has a degree of civilization in place, it is reason that offers the greatest hope for further reducing violence. ... Reason is up to these demands because it is an open-ended combinatorial system, an engine for generating an unlimited number of new ideas. Once it is programmed with a basic self-interest and an ability to communicate with others, its own logic will impel it, in the fullness of time, to respect the interests of ever-increasing numbers of others." - Steven Pinker
Returning to the terms of the Pacifist's Dilemma, the Escalator of Reason and the Expanding Circle change the game by blurring the lines between Player A and Player B. As one player increasingly empathizes with one player and vice versa, and reason abstracts the suffering as equally unjust for either side, the values in each outcome are summed together and the result is identical rewards or punishments for both players. This togetherness makes all but the mutual cooperation outcome a net loss, in essence merging the players into one and eliminating the dilemma.

If humanity has been developing its way toward peace, why are some of the most memorable slaughters in history from just the last century? Chroniclers of war often call the early to mid 1900s the Hemoclysm to describe the deluge of bloodletting in World Wars and genocidal episodes like Maoist China and Khmer Rouge Cambodia. In our revulsion to these massive immoralities it is important to remember that despite the vast number of people killed, the magnitudes of these atrocities are not exceptions that belie humanity as more violent than ever, but rather reflections of humanity as more populous than ever. (In 1800 there were one billion people on the planet, in 1900 that had almost doubled to just under two billion, and by 2000 the world population skyrocketed to over six billion.) In light of this striking variability in absolute numbers we need to instead consider the proportion of people affected if we are to look at long-term historical trends.

World Population
With proper perspective we see that modern societies experience only a tiny fraction of the violence that even the most peaceful of pre-state societies endured. Even factoring in egregious 20th century atrocities and World Wars does little to raise the overall percentages of violent death by comparison. Atrocitologist / necrometrician Matthew White's list of (Possibly) The Twenty (or so) Worst Things People Have Done to Each Other, reproduced in the section of the book addressing the common objection that the 20th century has been the worst yet, helps put our vivid cultural memories of the most recent atrocities into historical perspective. Of particular relevance is the adjusted ranking of the top twenty that Pinker provides, showing the surprising finding that the two most brutal 20th century episodes (WWII casualties and famine under Mao Zedong), while leading with the greatest absolute death tolls of the twenty (or so) listed, are only 9th and 11th respectively when ranked in terms of relative population killed. Meaning there are at least eight recorded events in our history before the 20th century that killed a greater percentage of the world's population. Living in pre-state societies, Pinker documents that you would have had anywhere from an average of 15 percent up to a 60 percent chance that your cause of death would have been that another man had killed you. Even living during the Second World War, your odds of dying violently during the worst of the 20th century (roughly the first half of it) are nowhere near, at around 2 percent. Today in the 21st century, western countries tally a rate of violent death at less than .01 percent, counting homicides as well as war deaths.

Since the end of World War II in 1945 man has been living in the "Long Peace", a dramatic near-cessation of major conflict, particularly among the dominant world powers (something new for them). In the past 20 years even other forms of extreme violence have declined, a recent period Pinker dubs the "New Peace", marked by a decrease in three forms of violence that many inaccurately assume to be increasing: civil & guerrilla wars, genocide, and terrorism.

An area histogram. The combined height of each stack represents the total of battle deaths for that year. Image credit: WSJ

There are important psychological reasons that we overestimate rates of violence that are actually in marked decline. One is the common assumption that violence in human society is metaphorically hydraulic: the amount of violence in the world is constant and only pushed around or pent up during peace before inevitably bursting into new conflict. Pinker makes it clear that this mental model is not supported by the facts, but the ready supply of hyperbolic news makes it hard to notice the overall trend without a step back to look at the whole analytically.

Other big reasons for our skewed exaggeration of present problems compared to past, cognitive tendencies I heard cited recently by Freakonomist Steven Levitt among many other social scientists, have to do with the magnitude of events and the ease with which we can remember them. People pay more attention to and ascribe disproportionately greater probability to the biggest, most intense events, which because of exponential population growth means that the 20th century had literally billions more potential victims. And as we saw earlier, the conflicts of the past hundred years take the top absolute tolls but are in line with relative tolls of destruction, the metric relevant to our comparison with the rest of history.

We live in a big world (that's big on media), so even the progressively tinier fraction of violence within it presents us with an absolute amount of violence too much for any one mind to handle. You could spend every waking hour consuming attention-grabbing news of civil strife, true crime shows, and terror ad infinitum. And some people do; you don't have to try hard to be exposed to media coverage of violence. How could anyone presented with such an onslaught of evidence for our capacity to commit violence think that we are becoming more peaceful? The human mind makes intuitive predictions based on the accessibility of examples in memory, which will naturally favor the vivid and recent examples. Without counter-balanced coverage (and the media much prefer the distressing to the mundane), we assign probabilities for the likelihood of future violence that are distorted by our shortsighted perspective of past violence. The result for most people is a gut reaction to reject any claim of human pacification (Pinker notes in the preface that immediate responses to his book's premise are typically "skepticism, incredulity, and sometimes anger", even from friends and family).

Image credit

It's hard to find real bones of contention to pick with "Better Angels". Steven Pinker maintains an equitable, analytical tone and sticks to credibly supported theses. But if I had to pick one to quibble over it would be in a challenge to the idea that 20th century disasters were coincidental bad luck, caused by the particularly bad apples Hitler, Stalin, and Mao. Granted, their killer combinations of charisma, ambition, and psychopathy persuaded millions to follow their incredibly destructive lead. And if only a critical decision point in history had gone the other way: Hitler killed in his 1930 auto crash, or Stalin assassinated, or Mao deciding that Marxism was kind of silly in the first place, maybe the world would have had been spared a few megadeaths in the 20th century ledger. Pinker is hardly the first or only scholar to ponder these counter-factuals, summarizing the position in a recent interview as: "Many historians have argued as follows: No Hitler, no Holocaust; no Stalin, no Purge; no Mao, no Great Leap Forward and Cultural Revolution." But the problem as I see it is our limited ability to continue pondering these counter-factual worlds beyond their theorized fork in time. I trust the historians know what they're talking about when they claim that the preemptive removal of these authoritarian leaders would have averted their ability to wreak their respective atrocities, but I'm not sure I trust any man to know with certitude what it would have been like even 5 or 10 years into such an alternate history. Like the defiantly unpredictable patterns of the weather driven by chaos theory, the further we extrapolate from a set of initial conditions the less we can predict about a dynamic system with confidence. Re-imagining the incredible systemic complexity that would be a world history without Hitler, Stalin, or Mao entails acknowledging the unforeseen possibility of alternatives equally if not more catastrophic. Pinker himself would be quick to point out that any bumps in the road to non-violence, Mao or no Mao, are only bumps in a clear downward trend. Why then, besides in wistful contemplation, entertain myopic fantasies of a smoother trend in the predictive isolation of Hitler-less 1940's Germany or Leap-less 1960's China? I'm not sure Steve gains anything for his main thesis in these counter-factual considerations.

Minor quibbles aside, "The Better Angels of Our Nature" assiduously justifies its subtitular contention: violence really has declined, and now it's not so hard to see why. Steven Pinker has assembled vast quantities of data to support his position, sourced in turn by the assemblies of other preeminent scholars in ethnography, anthropology, and the history of man. Add to this a trove of lab-tested social psychology, game theory, and the areas of Pinker's own expertise in cognitive psychology. The resulting dissertation, structured with the incredible skill and forethought that define Steven Pinker's books, sums these component analyses into the rational juggernaut needed to upend the conventional wisdom it is up against. Though consistently dispassionate in tone and bearing throughout, the title of this book betrays its emotional impact: optimism for humanity.

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