IT'S April 15th, tax day! (But not this year; this year, it's Emancipation Day, which is worth observing if anything is.) And probably not coincidentally, the movie adaptation of Ayn Rand's widely-loved and loathed novel "Atlas Shrugged" opens today at theatres nationwide. So what could be more appropriate and entertainingly polarising than a discussion of Ayn Rand's views on taxation?

Ayn Rand's position on government finance is unusual, to say the least. Rand was not an anarchist and believed in the possibility of a legitimate state, but did not believe in taxation. This left her in the odd and almost certainly untenable position of advocating a minimal state financed voluntarily. In her essay "Government Financing in a Free Society", Rand wrote:

In a fully free society, taxation—or, to be exact, payment for governmental services—would be voluntary. Since the proper services of a government—the police, the armed forces, the law courts—are demonstrably needed by individual citizens and affect their interests directly, the citizens would (and should) be willing to pay for such services, as they pay for insurance.

This is faintly ridiculous. From one side, the libertarian anarchist will agree that people are willing to pay for these services, but that a government monopoly in their provision will lead only to inefficiency and abuse. From the other side, the liberal statist will defend the government provision of the public goods Rand mentions, but will quite rightly argue that Rand seems not to grasp perhaps the main reason government coercion is needed, especially if one believes, as Rand does, that individuals ought to act in their rational self-interest.

It's true that we each benefit from the availability of genuinely public goods, but we benefit most if we are able to enjoy them without paying for them. A rationally self-interested individual will not voluntarily pay for public goods if she believes others will pay and she can get a free ride. But if we're all rationally self-interested, and we know we're all rationally self-interested, we know everyone else will also try to get a free ride, in which case it is doubly irrational to voluntarily pitch in. Even if you're not inclined to ride for free, why throw good money at an enterprise bound to fail? By threatening coercion against those who refuse to pay, the state establishes the conditions under which it would notbe pointless to pitch in—a condition in which you can be confident others will pitch in too. Tax collection solves the "assurance problem", as the game theorists call it.

Generally, Rand's moral and political philosophies run aground by failing to follow the correct but counterintuitve logic of the social contract tradition. The interests of individuals in society are best met when limits on self-interest are observed and enforced. At a sub-political level, the internalisation of moral constraints on self-interest is, seemingly paradoxically, a requirement of self-interest. At the political level, the artful application of state coercion overcomes the conflict and mis-coordination that prevail under conditions of "natural liberty" and establishes the peaceful and prosperous conditions of "civil liberty". It's worth adding that, in my opinion, the libertarian anarchist is right that if the public-goods argument justifies the services of the night-watchman state, it also justifies much more. In my opinion, the public-goods argument goes as far as justifying a scheme of social insurance that indemnifies individuals against a certain degree of bad fortune.

The implausibility of voluntary-financed government notwithstanding, elements of Rand's view remain profoundly appealing. For example:

The principle of voluntary government financing rests on the following premises: that the government is not the owner of the citizens' income and, therefore, cannot hold a blank check on that income—that the nature of the proper governmental services must be constitutionally defined and delimited, leaving the government no power to enlarge the scope of its services at its own arbitrary discretion. Consequently, the principle of voluntary government financing regards the government as the servant, not the ruler, of the citizens—as an agent who must be paid for his services, not as a benefactor whose services are gratuitous, who dispenses something for nothing.

The general view expressed here captures much of the reasonable moral core of the movement to restore and reinforce effective constitutional limits on government. Many Americans believe, not unreasonably, that far from acting always as an instrument that serves their interests, government often acts as if citizens' lives and labour are instruments to the special interests that control government. Indeed, the principle embedded in Mr Obama's budget speech, that tax increases are spending cuts, suggests the objectionable idea that allincome is government-owned, which it then "spends" by choosing not to hoover it up in taxes. To object to this way of picturing the relationship between citizens, their property, and their government is not to deny that the infrastructure of security, property and law maintained by government is necessary for a well-functioning economy that generates good jobs and decent incomes. It is necessary. But that infrastructure is for us. We are not for financing it. And we certainly aren't for financing whatever extraneous functions our continually mission-creeping government happens to have taken on. Necessary taxation is not theft. But there are margins at which taxation becomes difficult to distinguish from theft.

As Abraham Lincoln said so well, "The legitimate object of government, is to do for a community of people, whatever they need to have done, but can not do, at all, or can not, so well do, for themselves—in their separate, and individual capacities." Citizens reasonably resent a government that milks them to feed programmes that fail Lincoln's test. The inevitable problem in a democracy is that we disagree about which programmes those are. Some economists are fond of saying that "economics is not a morality play", but like it or not, our attitudes toward taxation are inevitably laden with moral assumptions. It doesn't help to ignore or casually dismiss them. It seems to me the quality and utility of our public discourse might improve were we to do a better job of making these assumptions explicit, and of seriously and respectfully considering whether our ideological opposites, be they socialists or "Atlas Shrugged" fans, might have one or two worthwhile points.

Now, pay up.