财经；自由兑换; 零和争论;

　　Economists are rethinking the view that capital should not be taxed;

　　经济学家正重新考虑是否要推翻不该对资本征税的观点。

　　Executives thunder that America's corporate-tax rates are to blame for economic weakness. Mitt Romney's campaign accuses Barack Obama of waging a “war on capital”. In fact, America's taxation of capital is more murky than confiscatory. At 39.2% (including state and local tax) its top corporate rate is the rich world's highest but loopholes mean most companies end up paying 27.6%, similar to Britain's effective rate of 27.4% and below Germany's 31.6%. America's tax rate on capital gains, at 15%, is lower than in many other countries. And if Mr Romney is the more ardent defender of capital, both men agree on the need for reforms. This is less a battle, more a skirmish.

　　行政当局愤怒指出美国经济疲软应归咎于公司企业所得税率。米特·罗姆尼发起一场运动指责奥巴马掀起了“对资本的战争”。事实上，美国的资本税与其用于没收充公，不如说其使用含混不明。其最高企业所得税税率高达39.2%（包括州政府和当地政府所征税收），居发达国家之首，不过由于存在漏洞，大多数公司最终支付的税率为27.6%，接近于英国的实际税率27.4%，低于德国的实际税率31.6%。美国的资本利得税税率为15%，比很多国家都要低。尽管罗姆尼更热衷于维护资本，他和奥巴马都认为有必要进行改革。这不像一场战争，反而只是一场小争论罢了。

　　The more interesting fight is going on within economics. For a generation, the profession's message on capital taxes has been simple: the lower the better. Most economists would prefer no tax on capital income at all. This seeming fanaticism is rooted in sensible models, developed in the 1970s and 1980s and built on a pleasing simplicity. Taxation inevitably involves trade-offs. Governments tax in order to fund public goods and limit inequality, but taxes are no free lunch. People and businesses respond—a tax on carrots, say, reduces carrot consumption—and these responses distort the economy and may reduce its potential growth rate.

　　经济学内部发生了更有趣的争执。一代以来，经济学家对于资本税的看法十分简单：税率越低越好。大多数经济学家根本不支持对资本收入征税。这种表面上的狂热植根于一些实用模型，它们于20世纪70年代到80年代发展起来，其基本特征是简洁，因此令人愉悦。税收不可避免地涉及了交换。政府征税是为了提供公共产品和限制收入不公，然而税收并非免费的午餐。个人和企业会提供反响，例如，对胡萝卜征税会减少胡萝卜的消费量，而这些反应使得经济扭曲，并有可能减少经济的潜在增长率。

　　In these models, inequality was seen as a problem of pay differences, best addressed through taxes on labour incomes. Taxes on capital were reckoned to have large costs. Capital, or savings invested in new production, raises future growth and consumption. If a tax on capital income discourages investment, that impact compounds indefinitely into the future. As a result, zero tax on capital income should be preferred, even by individuals who don't earn any such income. Economists became vocal in calling for reduced tax rates, and policymakers responded. Top capital-income tax rates in America and Britain fell by more than half from the 1950s to the 1980s. There is pressure to go further.

　　在这些模型中，人们认为收入的不一致导致出现了不公正，而解决这个问题的最好方法就是向劳力收入征税。资本税会产生巨额成本。资本，或者投入新生产的储蓄能够在未来带来经济增长和消费。若对资本收入征税会减少投资，其影响将有可能渗入到未来。这么一来，人们更乐于选择对资本收入征收零税收，即使对于那些并没有资本收入的人来说也是如此。经济学家强烈呼吁削减税率，并得到了政策制定者的回应。在20世纪50年代到80年代间，英美两国的最高资本收入税率下降了超过一半。若施加更多压力，还能降得更多。

　　But some economists are questioning the prevailing view, not least because reductions in capital-tax rates appear to have delivered more inequality than growth. In a 2008 paper, Juan Carlos Conesa of Universitat Autònoma de Barcelona, Sagiri Kitao of the University of Southern California and Dirk Krueger of the University of Pennsylvania argued that taxing capital was “not a bad idea after all”. Capital markets are imperfect, they observe, and households are unable to insure themselves against all of life's ups and downs. Taxing away some of the return to capital to provide social insurance against risks is appropriate.

　　不过一些经济学家正在质疑这种盛行的观点，其理由不仅仅是因为资本税率的减少似乎并未带来多少增长，反而扩大了不公正的发生。在一份2008年发布的论文上，巴塞罗那自治大学的Juan Carlos Conesa， 南加利福尼亚大学的Sagiri Kitao 以及宾夕法尼亚大学的Dirk Krueger争论说，对资本收入“绝不是一个坏主意”。在他们看来，资本市场是不完美的，单个家庭自身无力保证能够有效应对生命中的大起大落。因此通过征税拿走一部分资本收益，用以提供社会保障和抵御风险是合情合理的。

　　That is because the growth costs of capital taxes are overestimated. The old models contend that capital supply is highly sensitive to changes in tax policy, and that a zero tax rate is needed to prevent capital from drying up over the long run. This looks unrealistic, the authors reckon. Most capital-income taxes are paid by working-age adults saving for retirement, who will continue to save despite taxes. Stubborn savers make for a stable supply of investment capital, limiting the impact of taxes on growth. In the authors' estimation, a 36% capital-income tax rate is justified.

　　之所以发生这种情况，是因为资本税收的增长成本被高估了。旧模型坚持认为资本供给对税收政策的变化极其敏感，因此需要实行零税收以防止长期里资本陷入枯竭。作者们认为，这种说法是不切实际的。大多数资本收入税收是由在职成年人支付，用以积蓄养老，即便收税他们仍然会维持这种储蓄。坚定不移的储蓄者保证了投资性资本的稳定供给，这样就限制了税收对于经济增长带来的影响。在作者的预计中，36%的资本收入税率是公正的。

　　In a new NBER working paper, Thomas Piketty of the Paris School of Economics and Emmanuel Saez of the University of California at Berkeley poke different holes in the conventional view. The old models, they point out, ignore inheritances. In the real world inheritances strongly influence income levels, particularly among the very rich. Mr Romney recently reinforced this very point by exhorting students to borrow from parents if necessary. Taxes on wages and salaries are inadequate to the task of limiting inequality because they punish those who owe high incomes to greater ability and effort, rather than to inheritances. Messrs Piketty and Saez also question the scale of the threat to growth. They point to ratios of capital to output, which are surprisingly stable over time despite tax swings. Their model finds that the optimal tax rate on inheritance could be 50-60% or more.

　　在一份新的美国国家经济研究局（NBER）的工作报告中，巴黎经济学院的Thomas Piketty 和加利福尼亚大学伯克利分校的Emmanuel Saez 在传统的观点中找到了另外一些漏洞。他们指出，旧模型忽略了遗产的因素。在现实世界里，遗产强烈影响了收入水平，尤其是对于那些巨富来说更是如此。罗姆尼最近强调了这一点，他规劝学生们有必要的话可以向家长借钱。对工钱或薪水征税不足以限制收入不公，因为这些税收对因自身能力和努力工作而获得高收入的人造成了损害，反而放过了因遗产而暴富的人。Messrs Piketty 和Saez同样质疑了经济增长是否真的受到了那么大程度的威胁。他们显示了资本对产量的比率，发现就算税率变动，这一比率却能长期保持平稳，令人惊异。他们的模型发现对遗产征收的最佳税率能达到50%到60%，甚至更多。

　　Inheritance taxes are a minor source of government money, accounting for less than one percentage point of the 8-9% of GDP in revenues that Messrs Piketty and Saez estimate is raised by capital taxes. But taxing capital gains or corporate income, which is responsible for much of the rest, is also justifiable, they say. The often-fuzzy line between income from capital and labour means a large gap in relative tax rates breeds tax avoidance. When wage taxes are high and capital taxes are low, firms simply shift compensation from salaries to stock options and dividends, cutting revenue without boosting growth. All told, capital-tax rates as high or higher than those on labour may make sense, they think.

　　遗产税只是政府收入中极小的一个来源，在国内生产总值中占的比例不超过8%到9%，据Messrs Piketty 和Saez预计，征收资本税还可以提高这一收入。他们说，就连对资本增值或者企业所得征税，即资本税包含的另一部分，也是合理的。资本收入和劳力收入之间的界限经常模糊不清，这样在相对税率上产生了很大的差距，容易滋生漏税行为。若工资税高，资本税低，公司会将工资转为股权和红利，以此避免花费，这种行为减少了税收收入，无益于推动经济增长。他们认为，所有证据表明，资本税率同劳力税率一样高或者比后者高一点或许是合理的。

　　Pressure valve

　　压力阀

　　A recent paper by Emmanuel Farhi of Harvard University, Christopher Sleet and Sevin Yeltekin of Carnegie Mellon University, and Ivan Werning of the Massachusetts Institute of Technology makes another argument against abolition. The authors point out that rising inequality is a destabilising political force, which may encourage future governments to expropriate wealth through heavy taxation. That threat could discourage saving and investment now, something a weak economy cannot afford. Paradoxically, a progressive tax on capital in the present may lead to more investment by keeping inequality in check and by convincing firms that their wealth is (mostly) safe over the long term.

　　由哈佛大学的Emmanuel Farhi，卡内基梅隆大学的Christopher Sleet 和Sevin Yeltekin 以及麻省理工学院的Ivan Werning发表的一篇论文中针对取消资本税提出了另一项反证。这些作者指出，愈演愈烈的收入不公会造成政治不稳定，这样就会促使政府在未来通过征收重税来剥夺财富。这种威胁可能会对现在的储蓄和投资产生不利影响，而该影响是当前疲软的经济所无法承受的。矛盾的是，现在对资本渐进地征税或许会导致更多的投资，一方面，它能限制收入不公，另一方面，它可以使公司确信他们的财富在长期大部分都是安全的。

　　Fretting over high capital-tax rates still makes sense, not least because capital is highly mobile. If countries differ in their approach, firms may simply invest more in those with more congenial rates. But from a global perspective, as inequality rises, having taxes on capital income will look increasingly attractive—and, by some reckonings, more sensible than previously thought.

　　为了高资本税率烦恼不堪仍然是有道理的，尤其是因为资本具有高度的流动性。如若各国采取的政策不同，那么公司或许会仅仅凭借国家税率的友好程度选择投资方向。然而站在全球视角上来看，对资本收入征税看上去越来越吸引人了，并且在某些人看来，这比我们之前想的要合理多了。