Paul Krugman
I. MISTAKING BEAUTY FOR TRUTH
It’s hard to believe now, but not long ago economists were
congratulating themselves over the success of their field. Those
successes — or so they believed — were both theoretical and
practical, leading to a golden era for the profession. On the
theoretical side, they thought that they had resolved their internal
disputes. Thus, in a 2008 paper titled “The State of Macro” (that
is, macroeconomics, the study of big-picture issues like
recessions), Olivier Blanchard of M.I.T., now the chief economist
at the International Monetary Fund, declared that “the state of
macro is good.” The battles of yesteryear, he said, were over, and
there had been a “broad convergence of vision.” And in the real
world, economists believed they had things under control: the
“central problem of depression-prevention has been solved,”
declared Robert Lucas of the University of Chicago in his 2003
presidential address to the American Economic Association. In
2004, Ben Bernanke, a former Princeton professor who is now the
chairman of the Federal Reserve Board, celebrated the Great
Moderation in economic performance over the previous two
decades, which he attributed in part to improved economic policy
making.
CreditJason Lutes
Last year, everything came apart.
Few economists saw our current crisis coming, but this predictive
failure was the least of the field’s problems. More important was
the profession’s blindness to the very possibility of catastrophic
failures in a market economy. During the golden years, financial
economists came to believe that markets were inherently stable —
indeed, that stocks and other assets were always priced just right.
There was nothing in the prevailing models suggesting the
possibility of the kind of collapse that happened last year.
Meanwhile, macroeconomists were divided in their views. But the
main division was between those who insisted that free-market
economies never go astray and those who believed that economies
may stray now and then but that any major deviations from the
path of prosperity could and would be corrected by the allpowerful
Fed. Neither side was prepared to cope with an economy
that went off the rails despite the Fed’s best efforts.
And in the wake of the crisis, the fault lines in the economics
profession have yawned wider than ever. Lucas says the Obama
administration’s stimulus plans are “schlock economics,” and his
Chicago colleague John Cochrane says they’re based on
discredited “fairy tales.” In response, Brad DeLong of the
University of California, Berkeley, writes of the “intellectual
collapse” of the Chicago School, and I myself have written that
comments from Chicago economists are the product of a Dark
Age of macroeconomics in which hard-won knowledge has been
forgotten.
What happened to the economics profession? And where does it
go from here?
As I see it, the economics profession went astray because
economists, as a group, mistook beauty, clad in impressivelooking
mathematics, for truth. Until the Great Depression, most
economists clung to a vision of capitalism as a perfect or nearly
perfect system. That vision wasn’t sustainable in the face of mass
unemployment, but as memories of the Depression faded,
economists fell back in love with the old, idealized vision of an
economy in which rational individuals interact in perfect markets,
this time gussied up with fancy equations. The renewed romance
with the idealized market was, to be sure, partly a response to
shifting political winds, partly a response to financial incentives.
But while sabbaticals at the Hoover Institution and job
opportunities on Wall Street are nothing to sneeze at, the central
cause of the profession’s failure was the desire for an allencompassing,
intellectually elegant approach that also gave
economists a chance to show off their mathematical prowess.
Unfortunately, this romanticized and sanitized vision of the
economy led most economists to ignore all the things that can go
wrong. They turned a blind eye to the limitations of human
rationality that often lead to bubbles and busts; to the problems of
institutions that run amok; to the imperfections of markets —
especially financial markets — that can cause the economy’s
operating system to undergo sudden, unpredictable crashes; and
to the dangers created when regulators don’t believe in regulation.
It’s much harder to say where the economics profession goes from
here. But what’s almost certain is that economists will have to
learn to live with messiness. That is, they will have to
acknowledge the importance of irrational and often unpredictable
behavior, face up to the often idiosyncratic imperfections of
markets and accept that an elegant economic “theory of
everything” is a long way off. In practical terms, this will translate
into more cautious policy advice — and a reduced willingness to
dismantle economic safeguards in the faith that markets will solve
all problems.
II. FROM SMITH TO KEYNES AND BACK
The birth of economics as a discipline is usually credited to Adam
Smith, who published “The Wealth of Nations” in 1776. Over the
next 160 years an extensive body of economic theory was
developed, whose central message was: Trust the market. Yes,
economists admitted that there were cases in which markets
might fail, of which the most important was the case of
“externalities” — costs that people impose on others without
paying the price, like traffic congestion or pollution. But the basic
presumption of “neoclassical” economics (named after the late-
19th-century theorists who elaborated on the concepts of their
“classical” predecessors) was that we should have faith in the
market system.
This faith was, however, shattered by the Great Depression.
Actually, even in the face of total collapse some economists
insisted that whatever happens in a market economy must be
right: “Depressions are not simply evils,” declared Joseph
Schumpeter in 1934 — 1934! They are, he added, “forms of
something which has to be done.” But many, and eventually most,
economists turned to the insights of John Maynard Keynes for
both an explanation of what had happened and a solution to
future depressions.
Keynes did not, despite what you may have heard, want the
government to run the economy. He described his analysis in his
1936 masterwork, “The General Theory of Employment, Interest
and Money,” as “moderately conservative in its implications.” He
wanted to fix capitalism, not replace it. But he did challenge the
notion that free-market economies can function without a
minder, expressing particular contempt for financial markets,
which he viewed as being dominated by short-term speculation
with little regard for fundamentals. And he called for active
government intervention — printing more money and, if
necessary, spending heavily on public works — to fight
unemployment during slumps.
Photo
CreditJason Lutes
It’s important to understand that Keynes did much more than
make bold assertions. “The General Theory” is a work of
profound, deep analysis — analysis that persuaded the best young
economists of the day. Yet the story of economics over the past
half century is, to a large degree, the story of a retreat from
Keynesianism and a return to neoclassicism. The neoclassical
revival was initially led by Milton Friedman of the University of
Chicago, who asserted as early as 1953 that neoclassical
economics works well enough as a description of the way the
economy actually functions to be “both extremely fruitful and
deserving of much confidence.” But what about depressions?
Friedman’s counterattack against Keynes began with the doctrine
known as monetarism. Monetarists didn’t disagree in principle
with the idea that a market economy needs deliberate
stabilization. “We are all Keynesians now,” Friedman once said,
although he later claimed he was quoted out of context.
Monetarists asserted, however, that a very limited, circumscribed
form of government intervention — namely, instructing central
banks to keep the nation’s money supply, the sum of cash in
circulation and bank deposits, growing on a steady path — is all
that’s required to prevent depressions. Famously, Friedman and
his collaborator, Anna Schwartz, argued that if the Federal
Reserve had done its job properly, the Great Depression would
not have happened. Later, Friedman made a compelling case
against any deliberate effort by government to push
unemployment below its “natural” level (currently thought to be
about 4.8 percent in the United States): excessively expansionary
policies, he predicted, would lead to a combination of inflation
and high unemployment — a prediction that was borne out by the
stagflation of the 1970s, which greatly advanced the credibility of
the anti-Keynesian movement.
Eventually, however, the anti-Keynesian counterrevolution went
far beyond Friedman’s position, which came to seem relatively
moderate compared with what his successors were saying. Among
financial economists, Keynes’s disparaging vision of financial
markets as a “casino” was replaced by “efficient market” theory,
which asserted that financial markets always get asset prices right
given the available information. Meanwhile, many
macroeconomists completely rejected Keynes’s framework for
understanding economic slumps. Some returned to the view of
Schumpeter and other apologists for the Great Depression,
viewing recessions as a good thing, part of the economy’s
adjustment to change. And even those not willing to go that far
argued that any attempt to fight an economic slump would do
more harm than good.
Not all macroeconomists were willing to go down this road: many
became self-described New Keynesians, who continued to believe
in an active role for the government. Yet even they mostly
accepted the notion that investors and consumers are rational and
that markets generally get it right.
Of course, there were e
Paul KrugmanI. MISTAKING ความงามสำหรับความจริงมันยากที่จะเชื่อว่าตอนนี้ แต่ไม่นานนักเศรษฐศาสตร์ได้ศาสนิกเองผ่านความสำเร็จของความ ผู้ความสำเร็จ — หรือ เพื่อพวกเขาเชื่อว่าคือมีทั้งทฤษฎี และจริง นำไปสู่ยุคทองในอาชีพ ในการด้านทฤษฎี พวกเขาคิดว่า พวกเขาได้แก้ไขของพวกเขาภายในข้อโต้แย้ง ดังนั้น ในปี 2008 เป็น กระดาษชื่อ "รัฐแม" ได้คือ เศรษฐศาสตร์มหภาค การศึกษาปัญหาภาพใหญ่เช่นrecessions), Olivier Blanchard ของ M.I.T. ตอนนี้นักเศรษฐศาสตร์หัวหน้าที่นานาชาติเงินกองทุน ประกาศที่ "สถานะของแมโครเป็นดี" การต่อสู้ของเด็ก เขากล่าว มีกว่า และได้มีการ "กว้างบรรจบกันเห็น" และจริงโลก นักเศรษฐศาสตร์เชื่อว่า พวกเขามีสิ่งที่อยู่ภายใต้การควบคุม: การ"กลางปัญหาของภาวะซึมเศร้าป้องกันได้ถูกแก้ไขประกาศ Lucas โรเบิร์ตของมหาวิทยาลัยชิคาโกใน 2003 ของเขาประธานาธิบดีที่อยู่การเชื่อมโยงเศรษฐกิจอเมริกัน ในปี 2004, Ben Bernanke ศาสตราจารย์ปรินซ์ตันเดิมที่เป็นการประธานคณะกรรมการธนาคารกลาง เฉลิมฉลองดีดูแลในประสิทธิภาพทางเศรษฐกิจมากกว่าสองก่อนหน้านี้ทศวรรษที่ผ่านมา ซึ่งเขาบันทึกในส่วนนโยบายเศรษฐกิจที่ดีขึ้นทำให้CreditJason Lutesปี ทุกอย่างมาพร้อมกันนักเศรษฐศาสตร์ไม่เห็นของวิกฤตปัจจุบันที่มา แต่งานนี้ความล้มเหลวน้อยที่สุดของปัญหาของเขตข้อมูลได้ มีความสำคัญมากขึ้นthe profession’s blindness to the very possibility of catastrophicfailures in a market economy. During the golden years, financialeconomists came to believe that markets were inherently stable —indeed, that stocks and other assets were always priced just right.There was nothing in the prevailing models suggesting thepossibility of the kind of collapse that happened last year.Meanwhile, macroeconomists were divided in their views. But themain division was between those who insisted that free-marketeconomies never go astray and those who believed that economiesmay stray now and then but that any major deviations from thepath of prosperity could and would be corrected by the allpowerfulFed. Neither side was prepared to cope with an economythat went off the rails despite the Fed’s best efforts.And in the wake of the crisis, the fault lines in the economicsprofession have yawned wider than ever. Lucas says the Obamaadministration’s stimulus plans are “schlock economics,” and hisChicago colleague John Cochrane says they’re based on discredited “fairy tales.” In response, Brad DeLong of theUniversity of California, Berkeley, writes of the “intellectualcollapse” of the Chicago School, and I myself have written thatcomments from Chicago economists are the product of a DarkAge of macroeconomics in which hard-won knowledge has beenforgotten.What happened to the economics profession? And where does itไปจากที่นี่ไหมฉันเห็นมัน อาชีพเศรษฐศาสตร์ไปผู้เสียคนเพราะนักเศรษฐศาสตร์ เป็นกลุ่ม mistook งาม ห่มใน impressivelookingคณิตศาสตร์ ในความจริง จนถึงโรคซึมเศร้ามาก มากที่สุดนักเศรษฐศาสตร์พืชเพื่อวิสัยทัศน์ของทุนนิยมได้ หรือเกือบระบบสมบูรณ์แบบ วิสัยทัศน์ที่ไม่ยั่งยืนหน้ามวลว่างงาน แต่ เป็นความทรงจำของภาวะซึมเศร้า สีจางลงนักเศรษฐศาสตร์กลับลดลงรักเก่า idealized วิสัยทัศน์ของการเศรษฐกิจที่เชือดบุคคลโต้ตอบในตลาดโกขณะนี้ gussied ขึ้นกับสมการแฟนซี โรแมนซ์ต่ออายุกับตลาด idealized ได้ แน่ใจ บางส่วนเพื่อตอบสนองเลื่อนลอยลมทางการเมือง บางส่วนการตอบสนองต่อแรงจูงใจทางการเงินแต่ใน ขณะที่ sabbaticals สถาบันฮูเวอร์และงานโอกาสใน Wall Street ไม่จามที่ ใจกลางสาเหตุของความล้มเหลวในอาชีพที่มีความต้องการ allencompassingวิธีที่สง่างามสติปัญญาที่ยัง ให้นักเศรษฐศาสตร์ได้โอกาสที่จะอวดศักดาของคณิตศาสตร์อับ นี้ลี้ลับ และถูกสุขอนามัยวิสัยทัศน์ของการนักเศรษฐศาสตร์ส่วนใหญ่จะละเว้นทุกสิ่งที่สามารถไปนำเศรษฐกิจไม่ถูกต้อง พวกเขาเปิดตาคนตาบอดกับข้อจำกัดของมนุษย์rationality ที่มักจะทำให้ฟองอากาศและ busts ปัญหาของสถาบันที่ amok เพื่อความไม่สมบูรณ์ของตลาดเช่นตลาดการเงินโดยเฉพาะตัวที่สามารถทำให้เศรษฐกิจของระบบปฏิบัติการเพื่อรับการล้มเหลวอย่างฉับพลัน ไม่แน่นอน และto the dangers created when regulators don’t believe in regulation.It’s much harder to say where the economics profession goes fromhere. But what’s almost certain is that economists will have tolearn to live with messiness. That is, they will have toacknowledge the importance of irrational and often unpredictablebehavior, face up to the often idiosyncratic imperfections ofmarkets and accept that an elegant economic “theory ofeverything” is a long way off. In practical terms, this will translateinto more cautious policy advice — and a reduced willingness todismantle economic safeguards in the faith that markets will solveall problems.II. FROM SMITH TO KEYNES AND BACKThe birth of economics as a discipline is usually credited to AdamSmith, who published “The Wealth of Nations” in 1776. Over the next 160 years an extensive body of economic theory wasdeveloped, whose central message was: Trust the market. Yes,economists admitted that there were cases in which marketsmight fail, of which the most important was the case of“externalities” — costs that people impose on others withoutpaying the price, like traffic congestion or pollution. But the basicpresumption of “neoclassical” economics (named after the late-19th-century theorists who elaborated on the concepts of their“classical” predecessors) was that we should have faith in themarket system.This faith was, however, shattered by the Great Depression.Actually, even in the face of total collapse some economistsinsisted that whatever happens in a market economy must beright: “Depressions are not simply evils,” declared JosephSchumpeter in 1934 — 1934! They are, he added, “forms ofsomething which has to be done.” But many, and eventually most,economists turned to the insights of John Maynard Keynes forboth an explanation of what had happened and a solution tofuture depressions.Keynes did not, despite what you may have heard, want thegovernment to run the economy. He described his analysis in his1936 masterwork, “The General Theory of Employment, Interestand Money,” as “moderately conservative in its implications.” Hewanted to fix capitalism, not replace it. But he did challenge thenotion that free-market economies can function without aminder, expressing particular contempt for financial markets,which he viewed as being dominated by short-term speculationwith little regard for fundamentals. And he called for activegovernment intervention — printing more money and, ifnecessary, spending heavily on public works — to fightunemployment during slumps.PhotoCreditJason LutesIt’s important to understand that Keynes did much more thanmake bold assertions. “The General Theory” is a work of profound, deep analysis — analysis that persuaded the best youngeconomists of the day. Yet the story of economics over the pasthalf century is, to a large degree, the story of a retreat from
Keynesianism and a return to neoclassicism. The neoclassical
revival was initially led by Milton Friedman of the University of
Chicago, who asserted as early as 1953 that neoclassical
economics works well enough as a description of the way the
economy actually functions to be “both extremely fruitful and
deserving of much confidence.” But what about depressions?
Friedman’s counterattack against Keynes began with the doctrine
known as monetarism. Monetarists didn’t disagree in principle
with the idea that a market economy needs deliberate
stabilization. “We are all Keynesians now,” Friedman once said,
although he later claimed he was quoted out of context.
Monetarists asserted, however, that a very limited, circumscribed
form of government intervention — namely, instructing central
banks to keep the nation’s money supply, the sum of cash in
circulation and bank deposits, growing on a steady path — is all
that’s required to prevent depressions. Famously, Friedman and
his collaborator, Anna Schwartz, argued that if the Federal
Reserve had done its job properly, the Great Depression would
not have happened. Later, Friedman made a compelling case
against any deliberate effort by government to push
unemployment below its “natural” level (currently thought to be
about 4.8 percent in the United States): excessively expansionary
policies, he predicted, would lead to a combination of inflation
and high unemployment — a prediction that was borne out by the
stagflation of the 1970s, which greatly advanced the credibility of
the anti-Keynesian movement.
Eventually, however, the anti-Keynesian counterrevolution went
far beyond Friedman’s position, which came to seem relatively
moderate compared with what his successors were saying. Among
financial economists, Keynes’s disparaging vision of financial
markets as a “casino” was replaced by “efficient market” theory,
which asserted that financial markets always get asset prices right
given the available information. Meanwhile, many
macroeconomists completely rejected Keynes’s framework for
understanding economic slumps. Some returned to the view of
Schumpeter and other apologists for the Great Depression,
viewing recessions as a good thing, part of the economy’s
adjustment to change. And even those not willing to go that far
argued that any attempt to fight an economic slump would do
more harm than good.
Not all macroeconomists were willing to go down this road: many
became self-described New Keynesians, who continued to believe
in an active role for the government. Yet even they mostly
accepted the notion that investors and consumers are rational and
that markets generally get it right.
Of course, there were e
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