Over the last decade, Paul Slack has published a series of ground-breaking articles exploring the methodological and conceptual breadth of late seventeenth-century economic thought. He has shown how and for what purposes the earliest estimates of national income by William Petty and Gregory King were created, how political arithmetic promoted new ways of thinking about the state, and how contemporaries' recognition of rising living standards (‘material progress’) redefined early modern attitudes to luxury. This book extends the chronological breadth and analytical depth of this research agenda and employs a novel analytical framework for interpreting it: the culture of improvement.

Between 1570 and 1730, Slack insists, ‘improvement became a fundamental part of the national culture, governing how the English saw themselves and the condition of the nation to which they belonged, and their expectations of how it might alter in the future’ (p. 1). Improvement, which in the sixteenth century generally referred to the profitable cultivation of land, assumed a broader meaning during the seventeenth century thanks to Francis Bacon and his followers. Initially, improvement was extended to the educational sphere, for example in Bacon's Advancement of Learning (1605), but by 1700 the term was being applied to the ‘whole domain of human experience’ (p. 257).

The book is structured chronologically, albeit framed by two chapters exploring the contemporary evidence of improvement on the one hand (chapter 2), and the broader European context on the other (chapter 7). These chapters emphasise the distinctiveness of seventeenth-century England: the culture of improvement represented a break from England's past and from the paths followed by her European rivals. Partly this was an accident of language since ‘improvement’ not only acquired new meanings in the seventeenth century but also had no direct equivalent in other mainstream European languages. However, Slack also argues that the culture of improvement reflected England's peculiar cultural, economic and institutional conditions.

These conditions are examined in detail in the chronological chapters which form the core of the book (chapters 3–6). In chapter 3 Slack explains how the private benefits of improvement, notably increasing the profitability of land or acquiring patents of monopoly, were accommodated within Elizabethan civic humanism. He explores William Cecil's role in promoting the diversification of England's export trade. By the early seventeenth century tensions between private and public interests were surfacing due to the Crown's insatiable appetite for revenue. The failure of the 1614 Cockayne project, which had sought the ‘better improvement’ of the English drapery industry, severely weakened the case for ‘government intervention in the interests of the common weal’ (p. 82). An alternative economic doctrine, articulated by Thomas Mun and Edward Misselden, held that the balance of trade should be the focus of government policy. This doctrine, often referred to as mercantilism, provided a powerful defence of private self-interest by claiming that the commonwealth was nothing more than the private wealth of its individual members.

The political and constitutional upheavals of the mid-seventeenth century had a profound effect on improvement culture. Chapter 4 traces the intellectual contribution of the Hartlib circle, a network of correspondents drawn from across Europe, inspired by Bacon, who were committed to the improvement of knowledge. Various projects were tried with limited success, including educational institutions and poor law corporations. The Hartlib circle's enduring legacy was not institutional but cultural according to Slack. Walter Blith's influential English Improver (1649) advocated agricultural improvement, while William Petty's writings on political arithmetic from the 1660s provided new tools for measuring material improvement. Crucially for the purposes of Slack's argument, the Hartlib circle conceived of improvement as a never-ending process that would continue indefinitely.

The Hartlib circle's optimism, verging on utopianism, had to contend with the harsh economic and social realities of warfare. The Anglo–Dutch Wars and the wars against Louis XIV after 1689 posed a serious threat to the culture of improvement because they disrupted trade and consumed national wealth. Chapters 5 and 6 chart the shifting sands of opinion during this period and examine the most contested areas of debate between improvers and their opponents, including the balance of trade, interest rates, depopulation fears, luxury, the growth of London, poor law reform, empire, taxation and the national debt. Slack's exposition of these debates is masterly, but, as he acknowledges, improvement ‘had become a word of such general application that … it was impossible to pin down because it was everywhere and embraced everything’ (p. 212).

This observation, I would suggest, creates a tension in Slack's overall argument. In the concluding chapter Slack, following the Hartlib circle, defines improvement as ‘endless progress’ and nails his colours to the mast of Whig history (p. 263). However, it is not altogether clear that the advocates of improvement who came after the Hartlib circle endorsed this ‘strong’ version of improvement. Consider, for example, political arithmetic after Petty's death in 1687. Gregory King and Charles Davenant embraced Petty's national accounting framework but were considerably more equivocal than Petty when assessing the prospects for England's future improvement (pp. 163–4, 191–2, 197–8). This suggests that as improvement culture diffused more widely, it may have become less ambitious and more pragmatic. Although the Hartlib circle thought in terms of the improvement of knowledge ad infinitum, later writers discussed by Slack appear to have been more focused on short-term impediments to improvement such as warfare, infectious disease or the poor laws.

In other words, Slack's claim that ‘improvement never ended’ was not universally accepted in the mid-eighteenth century. Slack tacitly acknowledges this when he notes that Adam Smith and T. R. Malthus, though products of improvement culture, did not share Lord Macaulay's ‘insular and unqualified confidence in material progress’ (p. 264). This, it seems to me, is an important caveat since Smith's Wealth of Nations contains literally hundreds of references to improvement. As E. A. Wrigley has repeatedly emphasised, Smith thought that a country ‘which had acquired the full complement of riches’ would ‘advance no further’ owing to the fixed supply of land. Wrigley has shown how the use of coal enabled England to overcome the Smithian limits to growth. It would be fascinating to learn how Slack's improvement culture responded to, and shaped, industrial expansion after 1730.