EARLIER this month Tim Lee of the Washington Post tweeted:

People on the right view government pay as a symbolic/normative issue, private sector pay as a practical one. On the left it's the opposite. — Timothy B. Lee (@binarybits) July 12, 2013

I thought this was very insightful for a good half-hour. However, upon reflection, I think this is misleading, even as a rough sketch.

As a practical matter, everyone sees wage determination as a matter of both supply and demand and bargaining power. And I think everyone understands, at some level, that market forces affect bargaining power, and vice versa. The difference is one of emphasis, or analytic priority. For those on the right, supply and demand tends to be the dominant explanatory variable. For those on the left, bargaining power is the dominant explanatory variable.

As a normative matter, I think everyone thinks pay should be roughly proportional to the workers' contribution. However, there is disagreement about what ought to be taken into account when understanding a workers' contribution. People on the left are much more likely to see effort, time, the inherent human dignity of work, and the overall social value of the general enterprise all as part of the contribution and thus relevant to the question of proportional or just compensation. In contrast, people on the right are more likely to see the operation of supply and demand in competitive labour markets not only as the primary measure of the economic value of labour, but also as the primary measure of merit, or moral desert. The market wage just is the fair wage. It doesn't matter if the work is hard, or time-consuming, or socially necessary. If the market offers a pittance, then the work's objectively worth a pittance. The effort to claim more than a pittance is therefore an effort to unfairly claim more than is due. On the other side of the coin, if the market offers you an extravagant, princely sum, then that must be what you've got coming. A disproportionately high income-tax rate will seem obviously unfair.

This is a tidy worldview. To see what people deserve, just look at what they get. That is, as long as they get what the free market determines. The wages of public employees, set outside the "real" market, reflect special-interest politics, not supply and demand, and therefore are likely unmoored from the simple justice of the market.

Now, it would be nothing short of miraculous if wages in competitive labour markets happened to reflect all the things some people on the left think wages ought to reflect. But one needn't have mushy-headed metaphysical notions about what workers are due to find the right-leaning view laughably simplistic. Setting aside the normative matter of fairness in compensation, the key explanatory difference is that people on the left are more likely to see markets as creatures of politics, and to see wage-determination therefore as a combative process of political and legal bargaining. As a practical matter, your compensation is a matter of what you or your union can manage to claim through negotiation. As a symbolic/normative matter, insufficient bargaining power gets you screwed over; without enough bargaining power, you won't get your fair share, won't get your due. And this is true in both the public and private sector. With the decline of private-sector union power, the working classes have lost their practical ability to claim a decent share of profits, and therefore have gotten buggered by capital. Public-sector unions, on the other hand, have maintained the very practical power to successfully negotiate fair wages and benefits for government employees. That's why folks on the left find it so incredibly perverse that the right would so relentlessly attack public-sector unions, which they see as the only significant, effective force in the American economy keeping compensation more or less appropriate for a large swathe of workers. On the other end of the economic spectrum, the system is rigged to give private-sector executives undue bargaining power, resulting in outrageously high compensation out of all proportion with real contribution.

Let's return now to Mr Lee's tweet. The right seethes over public-sector pay while the left seethes over private-sector pay due to a disagreement over both the way wages are and ought to be determined. The right thinks the market pays people what they deserve, and so the government probably doesn't. Meanwhile, the left thinks the market will pay ordinary workers less than they deserve, unless their individual bargaining power is bolstered by a union. So de-unionised private-sector workers are getting screwed, whilst public-sector workers, though under fire, are faring pretty well. Isn't that the difference?