Coming soon: The Atlas of Ancient Rome

CarandiniThe Atlas of Ancient Rome, edited by Andrea Carandini, is a gorgeous, authoritative archeological survey of Rome from prehistory to the early medieval period. Transport yourself to antiquity with full-color maps, drawings, photos, and 3D reconstructions of the Eternal City, featuring descriptions of the fourteen regions of Rome and the urban history of each in unprecedented detail. Included are profiles and reconstructions of more than 500 major monuments and works of art, such as the Sanctuary of Vesta, the domus Augusti, and the Mausoleum of Augustus. This two-volume, slipcased edition examines the city’s topography and political-administrative divisions, trade and economic production, and social landscape and infrastructure using the most current archaeological findings and the latest mapping technologies. Take a look at a sampling of some of the detailed images from the book here, and be sure to mark your calendar for when this book becomes available in February 2017.

Cipher challenge #1 from Joshua Holden: Merkle’s Puzzles

The Mathematics of Secrets by Joshua Holden takes readers on a tour of the mathematics behind cryptography. Most books about cryptography are organized historically, or around how codes and ciphers have been used in government and military intelligence or bank transactions. Holden instead focuses on how mathematical principles underpin the ways that different codes and ciphers operate. Discussing the majority of ancient and modern ciphers currently known, The Mathematics of Secrets sheds light on both code making and code breaking. Over the next few weeks, we’ll be running a series of cipher challenges from Joshua Holden. Presenting the first, on Merkle’s puzzles. 

For over two thousand years, everyone assumed that before Alice and Bob start sending secret messages, they’d need to get together somewhere where an eavesdropper couldn’t overhear them in order to agree on the secret key they would use. In the fall of 1974, Ralph Merkle was an undergraduate at the University of California, Berkeley, and taking a class in computer security. He began wondering if there was a way around the assumption that everyone had always made. Was it possible for Alice to send Bob a message without having them agree on a key beforehand? Systems that do this are now called public-key cryptography, and they are a key ingredient in Internet commerce. Maybe Alice and Bob could agree on a key through some process that the eavesdropper couldn’t understand, even if she could overhear it.

Merkle’s idea, which is now commonly known as Merkle’s puzzles, was slow to be accepted and went through several revisions. Here is the version that was finally published. Alice starts by creating a large number of encrypted messages (the puzzles) and sends them to Bob.

The beginning of Merkle’s puzzles.

Merkle suggested that the encryption should be chosen so that breaking each puzzle by brute force is “tedious, but quite possible.” For our very small example, we will just use a cipher which shifts each letter in the message by a specified number of letters. Here are ten puzzles:


Alice explains to Bob that each puzzle consists of three sets of numbers. The first number is an ID number to identify the puzzle. The second set of numbers is a secret key from a more secure cipher which Alice and Bob could actually use to communicate. The last number is the same for all puzzles and is a check so that Bob can make sure he has solved the puzzle correctly. Finally, the puzzles are padded with random letters so that they are all the same length, and each puzzle is encrypted by shifting a different number of letters.

Bob picks one of the puzzles at random and solves it by a brute force search. He then sends Alice the ID number encrypted in the puzzle.

Bob solves the puzzle.

For example, if he picked the puzzle on the fifth line above, he might try shifting the letters:

zcktz etotk zkktz cktze lobky kbktl uaxyk bktzk ktgoz vabln
adlua fupul allua dluaf mpclz lclum vbyzl clual luhpa wbcmo
bemvb gvqvm bmmvb emvbg nqdma mdmvn wczam dmvbm mviqb xcdnp

qtbkq vkfkb qbbkq tbkqv cfsbp bsbkc lropb sbkqb bkxfq mrsce
ruclr wlglc rcclr uclrw dgtcq ctcld mspqc tclrc clygr nstdf
svdms xmhmd sddms vdmsx ehudr dudme ntqrd udmsd dmzhs otueg
twent ynine teent wenty fives evenf ourse vente enait puvfh

Now he knows the ID number is “twenty” and the secret key is 19, 25, 7, 4. He sends Alice “twenty”.

Alice has a list of the decrypted puzzles, sorted by ID number:

ID secret key check
zero nineteen ten seven twentyfive seventeen
one one six twenty fifteen seventeen
two nine five seventeen twelve seventeen
three five three ten nine seventeen
seventeen twenty seventeen nineteen sixteen seventeen
twenty nineteen twentyfive seven four seventeen
twentyfour ten one one seven seventeen

So she can also look up the secret key and find that it is 19, 25, 7, 4. Now Alice and Bob both know a secret key to a secure cipher, and they can start sending encrypted messages. (For examples of ciphers they might use, see Sections 1.6, 4.4, and 4.5 of The Mathematics of Secrets.)

Alice and Bob both have the secret key.

Can Eve the eavesdropper figure out the secret key? Let’s see what she has overheard. She has the encryptions of all of the puzzles, and the check number. She doesn’t know which puzzle Bob picked, but she does know that the ID number was “twenty”. And she doesn’t have Alice’s list of decrypted puzzles. It looks like she has to solve all of the puzzles before she can figure out which one Bob picked and get the secret key. This of course is possible, but will take her a lot longer than the procedure took Alice or Bob.

Eve can’t keep up.

Merkle’s puzzles were always a proof of concept — even Merkle knew that they wouldn’t work in practice. Alice and Bob’s advantage over Eve just isn’t large enough. Nevertheless, they had a direct impact on the development of public-key systems that are still very much in use on the Internet, such as the ones in Chapters 7 and 8 of The Mathematics of Secrets.

Actually, the version of Merkle’s puzzles that I’ve given here has a hole in it. The shift cipher has a weakness that lets Eve use Bob’s ID number to figure out which puzzle he solved without solving them herself. Can you use it to find the secret key which goes with ID number “ten”?

Dalton Conley & Jason Fletcher on how genomics is transforming the social sciences

GenomeSocial sciences have long been leery of genetics, but in the past decade, a small but intrepid group of economists, political scientists, and sociologists have harnessed the genomics revolution to paint a more complete picture of human social life. The Genome Factor shows how genomics is transforming the social sciences—and how social scientists are integrating both nature and nurture into a unified, comprehensive understanding of human behavior at both the individual and society-wide levels. The book raises pertinent questions: Can and should we target policies based on genotype? What evidence demonstrates how genes and environments work together to produce socioeconomic outcomes? Recently, The Genome Factor‘s authors, Dalton Conley and Jason Fletcher, answered some questions about their work.

What inspired you to write The Genome Factor?

JF: Our book discusses how findings and theories in genetics and biological sciences have shaped social science inquiry—the theories, methodologies, and interpretations of findings used in economics, sociology, political science, and related disciplines —both historically and in the newer era of molecular genetics. We have witnessed, and participated in, a period of rapid change and cross-pollination between the social and biological sciences. Our book draws out some of the major implications of this cross-pollination—we particularly focus on how new findings in genetics has overturned ideas and theories in the social sciences. We also use a critical eye to evaluate what social scientists and the broader public should believe about the overwhelming number of new findings produced in genetics.

What insights did you learn in writing the book?

JF: Genetics, the human genome project in particular, has been quite successful and influential in the past two decades, but has also experienced major setbacks and is still reeling from years of disappointments and a paradigm shift. There has been a major re-evaluation and resetting of expectations the clarity and power of genetic effects. Only 15 years ago, a main model was on the so-called OGOD model—one gene, one disease. While there are a few important examples where this model works, it has mostly failed. This failure has had wide implications on how genetic analysis is conducted as well as a rethinking of previous results; many of which are now thought to false findings. Now, much analysis is conducted using data 10s or 100s of thousands of people because the thinking is that most disease is caused by tens, hundreds, or even thousands of genes that each have a tiny effect. This shift has major implications for social science as well. It means genetic effects are diffuse and subtle, which makes it challenging to combine genetic and social science research. Genetics has also shifted from a science of mechanistic understanding to a large scale data mining enterprises. As social scientists, this approach is in opposition to our norms of producing evidence. This is something we will need to struggle through in the future.

How did you select the topics for the book chapters?

JF: We wanted to tackle big topics across multiple disciplines. We discuss some of the recent history of combining genetics and social science, before the molecular revolution when “genetics” were inferred from family relationships rather than measured directly. We then pivot to provide examples of cutting edge research in economics and sociology that has incorporated genetics to push social science inquiry forward. One example is the use of population genetic changes as a determinant of levels of economic development across the world. We also focus our attention to the near future and discuss how policy decisions may be affected by the inclusion of genetic data into social science and policy analysis. Can and should we target policies based on genotype? What evidence do we have that demonstrates how genes and environments work together to produce socioeconomic outcomes?

What impact do you hope The Genome Factor will have?

JF: We hope that readers see the promise as well as the perils of combining genetic and social science analysis. We provide a lot of examples of ongoing work, but also want to show the reader how we think about the larger issues that will remain as genetics progresses. We seek to show the reader how to look through a social science lens when thinking about genetic discoveries. This is a rapidly advancing field, so the particular examples we discuss will be out of date soon, but we want our broader ideas and lens to have longer staying power. As an example, advances in gene editing (CRISPR) have the potential to fundamentally transform genetic analysis. We discuss these gene editing discoveries in the context of some of their likely social impacts.

Dalton Conley is the Henry Putnam University Professor of Sociology at Princeton University. His many books include Parentology: Everything You Wanted to Know about the Science of Raising Children but Were Too Exhausted to Ask. He lives in New York City. Jason Fletcher is Professor of Public Affairs, Sociology, Agricultural and Applied Economics, and Population Health Sciences at the University of Wisconsin–Madison. He lives in Madison. They are the authors of The Genome Factor: What the Social Genomics Revolution Reveals about Ourselves, Our History, and the Future.

Kenneth Rogoff: Australia contemplates moving to a less cash society

RogoffToday in our blog series by Kenneth Rogoff, author of The Curse of Cash, Rogoff discusses Australia’s exploration of a less-cash society. Read other posts in the series here.

Recently, the Australian government stirred up a great deal of controversy by announcing the formation of task force to study the role of cash in the underground or “black” economy. There is no suggestion of an impetuous overnight change a la India, but rather a slow deliberative process. (For a recent review of The Curse of Cash with a special focus on the Indian context, see Businessline). Among other ideas, the task force is going to consider phasing out the Australian $100 bill (and presumably eventually the $50 in due time). It will also contemplate restrictions on the maximum size of cash purchases (as France, Italy, Spain, Greece and other European countries have done), and to wire cash registers to transmit sales information directly to the Treasury, as countries such as Sweden have done. According to the Minister for Revenue and Financial Services, Kelly O’Dwyer, the taskforce will have the full cooperation of the Federal police, immigration authorities, the Reserve Bank of Australia and financial regulators.

Of course, the issues with paper currency and how to mitigate them are the main topic of The Curse of Cash, which also provides historical context, data and institutional detail an an economic analysis of the issues. Australia is in many ways a very typical advanced economy when it comes to cash, with huge amounts of cash outstanding and unaccounted for, and mostly in the form of very large denomination notes. Roughly 93% of the Australian paper currency supply is in the form of $100 and $50 dollar bills (versus, say, 85% for the United States, and just over 90% for bills over 50 euro in the Euro area).

(Updated from The Curse of Cash, which goes through end 2015, when large notes constituted 92% of the money supply; all the data and figures for the book are posted here).

With 328 million $100s in circulation and 643 million $50s, there are roughly 14 $100 dollar bills for every man, woman and child in Australia, and roughly 27 $50s. As elsewhere, only a small fraction of these are accounted for.

Overall, the value of cash in circulation (70 billion Australian dollars) is a little over 4% of GDP, which puts Australia in the mainstream of advanced economies, about on par with the UK and Canada, and similar to the United States if USD held abroad are excluded. (See Figure 3.4 in The Curse of Cash).   

As in the US, cash is widely used for small transactions in Australia, accounting for 70% of transactions under $20 according to an April 2016 report by the Australian National Audit office in April 2016. But as in the United States, the importance of cash drops sharply for larger transactions – and that is even considering money washing back from the black economy into retail transactions. (See Figure 4.2 in The Curse of Cash).

Predictably, the Australian government announcement met with the usual tirades that equate getting rid of the large denomination notes with going cashless. This is polemic nonsense, readers of my book will know; I have also discussed the fundamental distinction in my blogs. Any legal fully tax-compliant transaction that ordinary citizens want to engage in can be executed easily enough with $20 bills (or even $10 bills), up to very large amounts. And smaller bills are also more than sufficient to satisfy ordinary people’s needs for privacy, the loss of big bills is a far greater detriment to those engaged in tax evasion and crime. Another strand of nonsense is that there must be better ways to increase tax compliance, such as lowering tax rates. (We can recall this from James Grant’s broadside rant in the Wall Street Journal.) Of course it would be good to improve the tax system, but tax evasion is always going to be an issue, and so will enforcement. And to the extent the government can collect a larger share of what it is owed from people who now avoid taxes by clever use of cash, then rates can be lowered for everyone else.

It is also nonsense to say that criminals and tax evaders will not feel the bite of a less cash society, and that they will effortlessly turn to other vehicles such as Bitcoin. There are good reasons why cash is king and why international law enforcement authorities find that cash is used somewhere along the line in almost every major criminal enterprise. Other vehicles simply cannot replicate its universality, convenience and liquidity. (Again, all this is discussed at length in the The Curse of Cash).

Not surprisingly, there has been pushback from the Reserve Bank of Australia, which argues that 5% of the cash banked by retailers is in 100s. This, of course, hardly matches up to the 45% of the cash supply that is 100s and more importantly, does not take into account that money from the black economy is routinely spent at retail stores. Many central banks are understandably reticent that a fall in the demand for cash will hurt their “seigniorage profits” from printing cash. The book discusses different conceptual approaches to measuring seigniorage. Perhaps the simplest measure is simply net new currency printed each year as a share of GDP). By this metric the Reserve Bank of Australia earned an average of .25% of GDP annually on average from 2006-2015, a very significant sum of money (see chapter 6.) But, as the book argues, the consolidated government (including the central bank) are likely losing even more through cash-facilitated tax evasion, and that does not even count the costs to the public of cash-facilitated crime.

The Australian authorities have noted that under-reporting of cash income has also distorted the welfare system (The Curse of Cash discusses this issue including evidence on Canada). Indeed, former senior Australian Reserve Bank official Peter Maier has argued that large denomination notes are widely hoarded by pensioners who aim to evade Australia’s mean-tested pension system. There are some tricky issues here having to do with privacy and tax fairness, but all in all, getting rid of big bills mainly hits those engaged in wholesale tax evasion and crime, not the poor. The Curse of Cash suggests low-cost approaches to financial inclusion to ensure that low-income families benefit beyond just reduction in crime.

Australia’s gradual and careful approach to dealing with cash is nothing like India’s radical policy, which aims at the same problems, but has created massive collateral damage. For a discussion of India, see here, here and here. The Australian cash commission’s report is due in October 2017; it is a welcome step. Given that Australia has been a huge innovator in currency (the Reserve Bank of Australia commission the first modern polymer notes that the UK and Canada have now adopted), it is encouraging that Australia is still willing to take the lead in the move to a less cash society.

Kenneth S. Rogoff, the Thomas D. Cabot Professor of Public Policy at Harvard University and former chief economist of the International Monetary Fund, is the coauthor of the New York Times bestseller This Time Is Different: Eight Centuries of Financial Folly (Princeton). He appears frequently in the national media and writes a monthly newspaper column that is syndicated in more than fifty countries. He lives in Cambridge, Massachusetts.

Find Kenneth Rogoff on Twitter: @krogoff

Browse our Economics & Finance 2017 Catalog

Our Economics & Finance 2017 catalog features new books from some of the most distinguished names in the field, including Kenneth S. Rogoff (co-author of This Time is Different) and Nobel Prize-winner Jean Tirole.

Browse the catalog below, or visit our stand at ASSA this weekend (1/6–1/8) in Chicago and pick up a copy in person: we’ll be at booths 107 and 109 with a full range of our books across the social sciences, we hope to see you there!

In The Curse of Cash, Kenneth S. Rogoff presents the startling argument that our economies are awash with too much cash. For most of us electronic transactions are increasingly supplanting cash, yet more cash is in circulation than ever before, much of it in large denomination bills that are rarely used in routine transactions. Instead, Rogoff argues, these large bills sustain a wide range of illegal activities ranging from tax evasion to terrorism, and we would be better off without them. Is it time to abolish the $100 bill?


Following his receipt of the Nobel Prize in 2014, Jean Tirole found himself cast into the role of public intellectual, regularly asked to comment on the issues of the day. In Economics for the Common Good Tirole takes to the role with gusto, issuing a clarion call to his fellow economists to join him in engaging in public debate, and applying his formidable knowledge to major issues ranging from unemployment to climate change and the digital revolution.

Economics for the Common Good by Jean Tirole

Economic inequality is an increasingly central and divisive issue in public life, but how can it be tackled? A sweeping survey covering human civilization since the Stone Age, Walter Scheidel’s The Great Leveler demonstrates that increased economic equality has typically followed in the wake of violent catastrophe: wars, revolutions, the collapse of states, and virulent plagues. Are peace and stability inexorably linked with economic inequality?

Scheidel Great Leveler jacket

Find out about these titles and many more in our Economics & Finance 2017 catalog.

Jeremi Suri: Is Trump blustering toward Armageddon?

Jeremi Suri, the editor for our America in the World series, has penned a powerful longform piece in The American Prospect, detailing how he thinks Trump could stumble into war:

“Trump will quickly and irretrievably lose control of his threats and commitments, and he will find himself pressured to pursue unwanted wars to preserve the very image of toughness that will get him into trouble in the first place. His belligerent deterrence will induce global war-fighting, as happened repeatedly during the Cold War. This time, the damage will be much greater and perhaps existential. We are witnessing the rapid demise of the American-led world order that for 70 years averted war among the largest states. The next few years, perhaps just the first year of the Trump presidency, will bring us to a dangerous new precipice in multiple parts of the globe. America doesn’t face the risk of war in just one theater of conflict. Under President Trump, the United States faces that risk in at least four separate theaters.”

Suri goes on to outline what he perceives as risks in several complicated strategic spaces: The Middle East, Europe, North Korea, and the South China Sea. Suri sets his warning in historical context, asking whether past precedent can offer a warning to current policy-makers. Read the full piece here.

Explore our America in the World series here.


The New Ecology

The New Ecology by Oswald J. SchmitzIn The New Ecology, Oswald Schmitz provides a concise guide to ecological thinking for an era in which the activity of one species—humans—has become the dominant influence on the environment, the Anthropocene. Much traditional ecological thinking has attempted to analyze the natural world in isolation from the social world of human life, regarding the human world as an external disturbance to the state of nature. The New Ecology seeks to bridge this nature/human divide and understand human life as an integral part of local and global ecosystems. In turn, it seeks also to recognize the scale of human influence on the environment and to promote an ethic of environmental stewardship, of responsible use and husbandry of the resources embodied in the ecosystem.

Two fields that might seem paradoxical areas of study for ecologists are industry and the city. One might think that the factory and the concrete jungle are as far removed from ecological concerns as one can get. However Schmitz points out that neither can be considered in isolation from either the natural world or the global economy, and that both can benefit from ecological thinking. Much modern industry is dependent on raw materials extracted through mining, raw materials which are necessarily finite in supply, meaning that in the long term these industries cannot be sustainable. Schmitz suggests that these industries could be reconfigured to mirror the cycles of food chains in which different organisms act to produce, to consume, and to decompose food to once again become raw material for the producers. To some extent, the practice of recycling follows this cycle, but we are a long way from recycling enough to supply all the raw materials needed for production. Massive quantities of these raw materials are being lost to landfill. One step in the right direction would be to design products with their ultimate decomposition in mind, to make it as easy as possible to break down and recycle the constituent materials. Taking things further, we can think of industries as making up complementary clusters in which, as in ecosystem food chains, the waste products from one industry become inputs for another. Schmitz notes the example of a development in Denmark in which “an electric power company, a pharmaceutical plant, a wall-board manufacturer, and an oil refinery exchange and use each other’s steam, gas, cooling water and gypsum residues.” (p.174) Another potential resource is the enormous quantities of raw materials embodied in our cities—could cities become the mines of the future?

Cities also need to be considered as their own distinct type of ecosystem. The urbanization of the global population continues; it is estimated that as much as 90% of the the world’s population will live in cities by the year 2100 (p.180). The sustainability of these cities will depend in part on the extent to which they can produce the materials needed for operation and minimize dependence on external resources. Thanks to ecological study we are increasingly aware of the vital role played by urban trees and greenspaces in filtering pollutants from the air, cooling the urban environment (in turn reducing energy use for cooling buildings), and controlling rainwater run-off. These unpaid services can be valued at hundred of thousands of dollars (p.184). But cities themselves form parts of larger systems, drawing on and affecting vast hinterlands, and often affecting distant parts of the globe in their demand for resources. Only through deepening our understanding of these complex interactions, including industrial and urban ecology, can we hope for long-term sustainability.

David Runciman on the new year’s challenges to democracy

In a video interview now featured on the London Review of Books homepage, David Runciman, author of The Confidence Trap, talks about Trump, Brexit and threats to democracy. Threats to democracy are nothing new; the US has survived threats ranging from the Great Depression to the Cuban missile crisis. Runciman shows that in fact, democracies are very good at recovering from emergencies, leading to the false belief that they are indestructible. In The Confidence Trap, Runciman argues that such complacency may lead to a crisis that is just too big to escape.

Read Runciman’s articles for the LRB from the past year:

Is this how democracy ends? · 1 December 2016

Untouchable? The Tory State · 8 September 2016

Where are we now? Responses to the Referendum · 14 July 2016

Short Cuts: the Coalition · 5 May 2016

Deliverology: Blair Hawks His Wares · 31 March 2016



Browse Our Mathematics 2017 Catalog

Be among the first to browse our Mathematics 2017 Catalog:

If you are heading to the 2017 Joint Mathematics Meetings in Atlanta, Georgia from January 4 to January 7, come visit us at booth #143 to enter daily book raffles, challenge the SET grand master in a SET match, and receive a free copy of The Joy of SET if you win! Please visit our booth for the schedule.

Also, follow #JMM17 and @PrincetonUnivPress on Twitter for updates and information on our new and forthcoming titles throughout the meeting.

Fibonacci helped to revive the West as the cradle of science, technology, and commerce, yet he vanished from the pages of history. Finding Fibonacci is Keith Devlin’s compelling firsthand account of his ten-year quest to tell Fibonacci’s story.

Devlin Fibonacci cover

This annual anthology brings together the year’s finest mathematics writing from around the world. Featuring promising new voices alongside some of the foremost names in the field, The Best Writing on Mathematics 2016 makes available to a wide audience many articles not easily found anywhere else—and you don’t need to be a mathematician to enjoy them.

Pitici Best writing on Maths

In The Calculus of Happiness, Oscar Fernandez shows us that math yields powerful insights into health, wealth, and love. Using only high-school-level math, he guides us through several of the surprising results, including an easy rule of thumb for choosing foods that lower our risk for developing diabetes, simple “all-weather” investment portfolios with great returns, and math-backed strategies for achieving financial independence and searching for our soul mate.

Fernandez Calculus of Happiness

If you would like updates of our new titles, subscribe to our newsletter.

Bird Fact Friday — Not so bird brained after all…

From page 161 of Bird Brain:

Bird Brain by Nathan Emery makes the case that birds are not as devoid of intelligence as has previously been thought. In fact, some can even be considered as smart as apes and dolphins. This concludes our Bird Fact Friday feature. Stay tuned for Horse Fact Friday starting in the new year!

Bird Brain
An Exploration of Avian Intelligence
Nathan Emery
With a foreword by Frans de Waal

EmeryBirds have not been known for their high IQs, which is why a person of questionable intelligence is sometimes called a “birdbrain.” Yet in the past two decades, the study of avian intelligence has witnessed dramatic advances. From a time when birds were seen as simple instinct machines responding only to stimuli in their external worlds, we now know that some birds have complex internal worlds as well. This beautifully illustrated book provides an engaging exploration of the avian mind, revealing how science is exploding one of the most widespread myths about our feathered friends—and changing the way we think about intelligence in other animals as well.

Bird Brain looks at the structures and functions of the avian brain, and describes the extraordinary behaviors that different types of avian intelligence give rise to. It offers insights into crows, jays, magpies, and other corvids—the “masterminds” of the avian world—as well as parrots and some less-studied species from around the world. This lively and accessible book shows how birds have sophisticated brains with abilities previously thought to be uniquely human, such as mental time travel, self-recognition, empathy, problem solving, imagination, and insight.

Written by a leading expert and featuring a foreword by Frans de Waal, renowned for his work on animal intelligence, Bird Brain shines critical new light on the mental lives of birds.