With all the complex differences among social thinkers as of a given time, and still more so over time, it is nevertheless possible to recognize certain key assumptions about human nature and about social causation which permit some to be grouped together as belonging to the constrained vision and others as belonging to the unconstrained vision. Although these groupings do not encompass all social theorists, they cover many important figures and enduring ideological conflicts of the past two centuries.
Running through the tradition of the unconstrained vision is the conviction that foolish or immoral choices explain the evils of the world—and that wiser or more moral and humane social policies are the solution. William Godwin's elaboration of this unconstrained vision in his Enquiry Concerning Political Justice drew upon and systematized such ideas found among numerous eighteenth-century thinkers—Jean-Jacques Rousseau, Voltaire, Condorcet, Thomas Paine, and D'Holbach being notable examples. This general approach was carried forth in the nineteenth century, in their very different ways, by Saint-Simon, Robert Owen, and by George Bernard Shaw and other Fabians. Its twentieth-century echoes are found in political theorists such as Harold Laski, in economists like Thorstein Veblen and John Kenneth Galbraith, and in the law with a whole school of advocates of judicial activism, epitomized by Ronald Dworkin in theory and Earl Warren in practice.
By contrast, the constrained vision sees the evils of the world as deriving from the limited and unhappy choices available, given the inherent moral and intellectual limitations of human beings. For amelioration of these evils and the promotion of progress, they rely on the systemic characteristics of certain social processes such as moral traditions, the marketplace, or families. They conceive of these processes as evolved rather than designed—and rely on these general patterns of social interaction rather than on specific policy designed to directly produce particular results for particular individuals and groups. This constrained view of human capacities found in Adam Smith is also found in a long series of other social thinkers, ranging from Thomas Hobbes in the seventeenth century, through Edmund Burke and the authors of The Federalist Papers among Smith's contemporaries, through such twentieth-century figures as Oliver Wendell Holmes in law, Milton Friedman in economics, and Friedrich A. Hayek in general social theory.
Not all social thinkers fit this schematic dichotomy. John Stuart Mill and Karl Marx, for example, do not fit, for very different reasons. . . . Others take midway positions between the two visions, or convert from one to the other. However, the conflict of visions is no less real because everyone has not chosen sides or irrevocably committed themselves.
(Thomas Sowell, A Conflict of Visions: Ideological Origins of Political Struggles [New York: Basic Books, 2002], 31-2 [ellipsis added])
Note from KBJ: For some odd reason, Sowell prefers "the unconstrained vision" to "progressivism" and "the constrained vision" to "conservatism." Perhaps he thinks the terms "progressivism" and "conservatism" are so ambiguous or vague as to be useless. If so, I disagree.
