Sometimes the deepest differences in politics aren't about the conclusions people draw but the way they reach them.

The British statesman Edmund Burke and the Anglo-American revolutionary Thomas Paine both favored free trade, for example, but for different reasons. The radical Paine believed that free trade would spread rationality and enlightenment and thus help bring war and tyranny to an end. The conservative Burke thought that government interference with trade would likely do more harm than good.

The difference in outlook between the two men, as Yuval Levin argues in a fine new book called "The Great Debate," underlies much of our politics more than 200 years after they wrote their pamphlets and essays.

The debate Levin describes is a family quarrel within liberalism. Both sides have sought to advance liberty as they understood it. Paine's progressive version of liberalism championed the Enlightenment as a set of newly discovered principles for political life that needed only to be followed. Burke's conservative version, on the other hand, thought liberty and equality were cultural achievements "built up over countless generations of social trial and error."

For Paine, the discovery that all people by nature have equal rights meant that we no longer needed to learn from the political practices of the past. To defer to the alleged wisdom of our forebears would amount to letting the dead govern us as they had themselves. Each generation should make its own choices.

So should each individual. Paine's thought often seems to evince a desire to free the individual from history, community and traditional religion. That desire eventually led him to advocate a mini welfare state that he thought would let liberated individuals flourish. He wanted to tax inheritances — the unequal past — to pay for it. Paine also vehemently denied that the basic political questions were complicated. So he thought there would be no need for political parties once enlightened principles had triumphed, or for checks and balances.

Burke agreed with none of this. It made no sense to him to think of the individual in isolation from his community and its history, as in a hypothetical "state of nature." Each of us is defined not only by choices but also by obligations, many of them unchosen — notably our obligations to children, parents and siblings. Balancing liberty and order was an extremely precarious achievement. Trying to fix a society's defects could threaten its stability, and abstract principles wouldn't go very far in identifying a way forward. Hence party politics would never be transcended. There would always be disagreement about how to pursue the common good.

Burke was a reformer, not someone who resisted all change. He defended the rights of Catholics and Indians, sought to soften criminal penalties, and fought corruption and waste in the royal household. As Levin astutely notes, Burke made more room for change than Paine did. Paine thought governments would need only minor modifications after the basic questions were settled. Burke saw no such endpoint.

Both men agreed on American independence from Britain, but for characteristically different reasons. Burke thought the British government had alienated the colonists by insisting on its rights over them in an unwise way. Paine saw the American Revolution more grandly: as the first great political triumph for liberal principles, one that would be repeated worldwide.

Levin's sympathies are with Burke, but he presents the arguments fairly enough that readers — especially American readers contemplating the follies of a hereditary monarchy — will often side with Paine. Many of his ideas, more than Burke's, are in the American bloodstream.

Levin sees today's health care debate in light of these opposing outlooks. There is an echo of Paine in the confidence that enlightened people can reorganize a big chunk of our world by applying reason. (President Obama recently confessed that this had turned out to be trickier than he had expected.) On the other side, skeptics argue for a more modest set of improvements to our system, hoping that these reforms will enable more learning by trial and error.

Yet Levin also notes that conservatives have often sounded much like Paine themselves. President Ronald Reagan explicitly quoted Paine's wildly unconservative line that "we have it in our power to begin the world anew." Levin suggests that the practice of conservatism has been more Burkean than its arguments. The arguments have, however, weakened the practice. To use an example Levin does not, President George W. Bush's confidence that Iraq was fertile soil for republican government owed more to Paine than to Burke. More generally, conservatives have sometimes been attracted to the apparent simplicity of principle rather than paying attention to the details of policy.

It would be ambitious enough for a book to seek to reinterpret the history of our political debates, as Levin's does. Implicitly, though, he is seeking to do something more than that: He is trying to reground American conservatism.