The Cambridge historian Lord Acton (1834-1902) – who is best remembered for his maxim “Power tends to corrupt, and absolute power corrupts absolutely” – spent much of his professional life working on a single book, a comprehensive history of liberty. As one of the most knowledgeable historians of the nineteenth century, Acton was uniquely qualified for this ambitious project. Unfortunately, however, his rigorous standards of scholarship eventually got the better of him.

Distrustful of secondary accounts, Acton insisted on doing original research in every phase of his history. And since his history spanned over 2500 years, covered many different countries, and dealt with everything from the history of religion and philosophy to the history of political movements, it became virtually impossible for any one person, however brilliant and industrious, to complete the task that Acton had set for himself. Consequently, Acton’s masterpiece was never finished, and his history of liberty, the work of a lifetime, became known as “the greatest book never written.”

Although Acton never published a book, he did write many articles that reflected his passionate interest in the history of freedom, religious toleration, and constitutional government. According to Acton, we cannot understand the history of Western civilization if we fail to appreciate the perennial conflict between liberty and power. The idea of liberty, he said, “is the unity, the only unity of the history of the world, and the one principle of a philosophy of history.”

Acton detected something unique in Western civilization, a distinctive worldview that set it apart from other cultures. In this worldview, which took centuries to develop, the individual was afforded a status greater than any collective entity, such as the state or society; and the individual conscience, especially in religious matters, came to be treated as a supreme value that should remain forever immune to the incursions of power.

Throughout his articles, we see many indications of Acton’s primary interest, namely to explain the various factors that contributed to the rise of freedom in Western civilization. What were the ideological conditions that led so many Western intellectuals to focus their attention on the idea of freedom? And what were the social and political conditions that made it possible to transform the idea of freedom into specific institutions? According to Acton, if we wish to understand the causes of freedom we must look beneath the surface of recent events to its roots in the intellectual, social, and political history of the Western world.

When Thomas Jefferson, John Adams and others in their tradition referred to history as “the lamp of experience,” they were expressing an insight with which Acton agreed. There is an important sense in which we can understand past ages better than our own. For example, when Edward Gibbon wrote The Decline and Fall of the Roman Empire he was dealing with events that had happened some 1500 years earlier. Yet this distance of time, though disadvantageous in some respects, enabled Gibbon to view the arc of Roman history from a perspective that would have been impossible for a historian living, say, in the year 300, in the heart of Rome itself.

Similarly, a historian living a century from now could probably write a better history of modern libertarianism than we can at present, even though we are able to experience events as they happen, in a way the future historian cannot. What the future historian will have, and what we presently lack, is an overall perspective of how things will eventually turn out – which libertarian ideas and policies will be able to gain popular support, which libertarian institutions will prove most effective, and so forth. We are simply too close to these things at present to be able to render a final judgment; and, unlike the future historian, we cannot know where our current efforts will take us.

This is why modern libertarians, like our eighteenth-century predecessors, must rely on a knowledge of freedom’s history for our own “lamp of experience.” And here we are especially fortunate to have a historian of Acton’s caliber to guide us.

Two of Acton’s essays are especially relevant in this context. The first, “The History of Freedom in Antiquity,” stresses the intellectual history of freedom, whereas the second, “The History of Freedom in Christianity,” focuses on the institutional history of freedom. Before exploring the significance of this distinction, we would do well to ponder a few of Acton’s incisive observations. In “The History of Freedom in Antiquity,” Acton wrote:

At all times sincere friends of freedom have been rare, and its triumphs have been due to minorities, that have prevailed by associating themselves with auxiliaries whose objects often differed from their own; and this association, which is always dangerous, has been sometimes disastrous, by giving to opponents just grounds of opposition, and by kindling dispute over the spoils in the hour of success.

This passage raises a number of interesting issues that I cannot explore here. I quoted it to illustrate the principle that even a little knowledge of freedom’s history can shed light on its future prospects. Modern libertarians, for example, regard themselves as among those “sincere friends of freedom” who, according to Acton, have always been in the minority. Thus, rather than viewing our minority status as cause for pessimism, we should understand that this has been the norm throughout history. A minority status, according to Acton, has not presented an insuperable barrier to the progress of freedom. Of course, history, as they say, is not destiny, so Acton’s observation doesn’t prove anything one way or the other. But it may suggest new ways of looking at old problems.

Immediately after the passage I just quoted, Acton wrote:

No obstacle has been so constant, or so difficult to overcome, as uncertainty and confusion touching the nature of true liberty. If hostile interests have wrought much injury, false ideas have wrought still more; and its advance is recorded in the increase of knowledge, as much as in the improvement of laws. The history of institutions is often a history of deception and illusions; for their virtue depends on the ideas that produce and on the spirit that preserves them, and the form may remain unaltered when the substance has passed away.

As is so typical of Acton’s writing, this passage bears the mark of extensive research and reflection, condensing a number of important ideas into a few lines. Perhaps most important for our purpose is Acton’s point about the significance of ideas and their relationship to institutions.

Essentially, Acton was saying that political institutions alone cannot be relied upon to preserve freedom, because such institutions have no real substance apart from the ideas that people have about them. A political institution, such as the American presidency, may retain the same external characteristics through time; officially, for example, the office of president had the same powers during the latter half of the nineteenth century, when Acton was writing, that it had during the Washington administration. But, as Acton pointed out, the reality of power is often far different from what it appears to be on paper:

Legally and to outward seeming the American President is the successor of Washington, and still enjoys power devised and limited by the Convention of Philadelphia. In reality the new President differs from the Magistrate imagined by the fathers of the Republic as widely as Monarchy from Democracy, for he is expected to make 70,000 changes in the public service; fifty years ago John Quincy Adams dismissed only two men.

It is interesting to note that a similar point had been made many years earlier by James Madison about the separation of powers in the federal government. The system of checks and balances was supposed to pit each branch of the government against the other two, which in turn was supposed to inhibit the pursuit of power by the members of each branch and thereby restrain the growth of centralized government. But some years after the Constitution had become the law of the land, Madison, who is often hailed as the father of that document, had serious second thoughts about the effectiveness of this system. Indeed, Madison later characterized the separation of powers, as specified in the Constitution, as nothing more than a “parchment barrier” to the growth of the federal government. The idea of checks and balances looked good on paper, but that was about all. It would not serve to restrain the growth of government in fact, because each branch – whether executive, legislative, or judicial – would ultimately seek to expand its power not by encroaching on the jurisdiction of the other branches but by taking freedom away from the people at large.

Acton was calling attention to a kind of optical illusion that can be generated by political institutions. As long as these institutions appear to be in good working order, then it is frequently assumed that our freedom is secure and that we needn’t worry about the onset of despotism. Yet even a political institution that originally served the interests of liberty can insensibly degenerate over time into an instrument of power – and this can happen with no external changes in the formal characteristics of that institution. This is what Acton meant when he said that “the history of institutions is often a history of deception and illusions,” and that the form of an institution “may remain unaltered when the substance has passed away.”

Acton’s other claim—that the “virtue [of institutions] depends on the ideas that produce and on the spirit that preserves them”—illustrates his belief in the crucial role of ideas in achieving and maintaining a free society. However much political institutions that were originally designed to preserve freedom may have been corrupted and turned to other uses, it may still be possible to restore their original spirit with fresh ideas about freedom. If institutions can be corrupted with bad ideas, they can also be reinvigorated with good ideas.