A Brief History of Liberty, David Schmidtz and Jason Brennan (Wiley-Blackwell) £17.99/$29.95 (pb)

Is the world freer now than it was fifty years ago? Was it freer fifty years ago than it was in the sixteenth century or in antiquity or in prehistoric times? Do these questions make sense? And even if they do, is it necessarily better to have more freedom than to have less? According to David Schmidtz and Jason Brennan, the answer to all of these questions is, broadly speaking, “Yes”.

Schmidtz and Brennan have written what they call a “history of liberty”, which is not, they point out, the same thing as a history of theorising about liberty. In other words, their book is not about the history of philosophy; rather, it is about history. Nevertheless, this particular history is of interest to philosophers because it traces the development of a phenomenon about which philosophers have debated endlessly.

Why should a history of liberty be of interest to philosophers if the latter are concerned above all to understand what liberty is? Isn’t the philosophical question of the nature of liberty logically prior to, and therefore unaffected by, any set of empirical claims about the historical conditions under which liberty is favoured or threatened?

The answer to this objection is that, at least for a good number of contemporary political philosophers, we cannot fully understand the nature of liberty without also having knowledge of certain general empirical facts about how societies evolve and about which kinds of institutions are the most efficient or stable. Moreover, it is difficult to theorise fruitfully about the value of liberty without some knowledge about social causation at the macro-level. Is liberty an end in itself? If so, which goods tend to produce liberty? Or should we say that liberty has only instrumental value? If so, as a means to what?

Before beginning their story, Schmidtz and Brennan set out and discuss a variety of possible meanings of liberty (or freedom, which for them amounts the same thing). Roughly speaking, they identify two salient meanings: negative freedom, understood as the absence of interference by other agents (a phenomenon particularly prized by liberals), and positive freedom, understood primarily as the range of “real” choice open to a person. To illustrate this basic distinction: I am negatively free to fly from Britain to China if, were I to try, no one would stop me from doing so; I am positively free to do so if, in addition, aeroplanes have been invented and produced, one of them is about to fly to China, and I have enough money to buy a ticket. Also relevant, however, is the idea of positive freedom as self-control or self-mastery, a version of which is discussed in the final chapter.

As a piece of conceptual analysis, this preliminary discussion is somewhat cursory. Its brevity and simplicity is perhaps understandable, given the historical focus and ambitious scope of the book, and the authors’ evident desire to get the light, entertaining and up-beat narrative moving.

According to Schmidtz and Brennan, crucial among the historical conditions of liberty are the development of commerce and the rule of law. Commerce under the rule of law leads to innovation, prosperity, and a new kind of self-sufficiency: “people can produce enough to meet their own needs by producing enough to meet other people’s needs.” It promotes stable expectations, interdependence, and peace. Commercial societies have always tended to be the most tolerant societies.

It is in such societies, Schmidtz and Brennan argue, that we witness the historical development of religious and civil liberties. Commercial societies have often been criticised as promoting selfishness, inequality and exploitation; nevertheless, say Schmidtz and Brennan, if you are seeking “top-quality criticism” of commercial societies, the places to go are “London, New York, or Boston – not Pyongyang, Havana or even Moscow.”

Although the book has a strongly classical liberal flavour, it also contains some interesting discussion of positive liberty. For one thing, Schmidtz and Brennan argue that the progress of negative liberty in western societies has massively expanded almost everyone’s range of real options. For another, they suggest that this greater (negative and positive) external freedom can open the way to a greater internal or “psychological” freedom.

Psychological freedom – which Schmidtz and Brennan call “the last frontier” – is sometimes held to be hampered by the existence of an excessively large range of external options. Can we cope, psychologically, with so many alternatives? Were humans not happier, better able to deliberate effectively, and therefore less constrained internally, when their options were more limited externally?

Schmidtz and Brennan are again optimistic. The psychological pressures brought on by our increased external freedom – our disorientation in the face of a plethora of options, our seemingly irremovable desire continually to maximise our own achievements, and so on – are indeed forms of internal constraint, but we have the internal resources to control and overcome them. We are simply not as fragile or impotent as anti-liberal philosophers would have us believe.

Ian Carter is associate professor of political philosophy at the University of Pavia, Italy

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