New York Times op-ed, How to Break Bread With the Republicans, by N. Gregory Mankiw (Harvard University, Department of Economics):

Dear President Obama:

Sorry to bother you. I know you are busy. But I have the sense that you could use a few words of advice. … As a sometime adviser to Republicans, I’d like to offer a few guidelines to understanding their approach to economic policy. Follow these rules of thumb and your job will be a lot easier.

Think at the Margin.  Republicans worry about the adverse incentive effects of high marginal tax rates. A marginal tax rate is the additional tax that a person pays on an extra dollar of income. … From the standpoint of incentives, a tax cut is worthy of its name only if it increases the reward for earning additional income.

Stop Trying to Spread the Wealth.  Ever since your famous exchange with Joe the Plumber, it has been clear that you believe that the redistribution of income is a crucial function of government. A long philosophical tradition supports your view. It includes John Rawls’s treatise A Theory of Justice, which concludes that the main goal of public policy should be to transfer resources to those at the bottom of the economic ladder.

Many Republicans, however, reject this view of the state. From their perspective, it is not the proper role of government to fix the income distribution in an attempt to achieve some utopian vision of fairness. They believe, instead, that in a free society, people make money when they produce goods and services that others value, and that, as a result, what they earn is rightfully theirs. This view also has a long intellectual tradition. The libertarian philosopher Robert Nozick has suggested revising the old leftist slogan “From each according to his ability, to each according to his needs” to “From each as they choose, to each as they are chosen.”

Spread Opportunity Instead.  Despite their rejection of spreading the wealth, Republicans recognize that times are hard for the less fortunate. Their solution is not to adjust the slices of the economic pie, as if they had been doled out by careless cutting, but to expand the pie by providing greater opportunity for all. Since the mid-1970s, the gap between rich and poor has grown considerably. One of best analyses of this long-term trend is by the Harvard economics professors Claudia Goldin and Lawrence Katz in their book, The Race Between Education and Technology. The authors conclude that widening inequality is largely a symptom of the educational system’s failure to provide enough skilled workers to keep up with the ever increasing demand.  Educational reform, therefore, should be a high priority.