It is a question often asked: what do Ricardo and Marx have to say about interpersonal inequality of income? The answer is, strictly speaking, very little. In writings of neither Ricardo nor Marx does inequality in personal incomes feature at all, and I even think that the concept of what we call “interpersonal inequality” or “size distribution of incomes” does not appear.
The reason why this is the case is both simple and revealing. Ricardo and Marx were concerned with functional (between factors of production) distribution of income, that is with the distribution of net product between workers, capitalists and landlords (the three big classes introduced by Adam Smith). In Ricardo, this concern was such that he wrote on page 1 of The Principles, the famous sentence that the principal problem of political economy is to study the distribution between “proprietors of land, the owners…of capital and the labourers”. Actually, the entire book is organized around that idea. Marx likewise (with a few exceptions) dealt with functional distribution only.
The omission of interpersonal distribution is revealing of the type of society that Ricardo and Marx had in mind. To see this consider the decomposition of a standard inequality measure like Gini coefficient. It is decomposed into three components: the gap between mean incomes of different groups into which we break a society, inequality within each of these groups, and the “overlap” term which is non-zero when some members of a mean-poorer group have higher incomes than some members of a mean-richer group.
Now, consider a society which is strictly segregated into classes such that (say) capitalists are rich and workers are poor. Interpersonal inequality looked at through the lenses of a Gini coefficient will not include the overlap term because of a tacit assumption shared by both Ricardo and Marx that all capitalists are richer than all workers (and if landlords are included that they are richer than the other two groups). If in addition, all workers are paid subsistence, the within-group inequality for them will be zero. Capitalists and landlords may be differentiated depending on how much capital or land each possesses but because of their small population size, they will not add much to inequality (Gini within each group is weighed by the group income and population shares).
The bottom line is that most of interpersonal inequality will boil down to the gaps in mean incomes between the two (or if landlords are included, three) classes. Studying only that is not different from being concerned with income shares of the three groups, that is, with functional income distribution. Thus the question of income inequality between individuals dissolves into the question of income shares of landlords, capitalists and workers. In such a society, it is indeed of little practical import to go beyond functional distribution.
This picture which is, I think, basically accurate is a bit simplified, especially as far as Marx is concerned. In Ricardo workers are seen as a homogeneous mass facing capitalists such that every increase in the wage rate implies a direct reduction in profit: “a rise of wages, from the circumstance of laborer being more liberally rewarded, or from the difficulty of procuring necessities on which wages are expended, does not…produce a rise in prices but has a great effect in lowering profits” (Principles, Chapter I, Section VII, p. 31). Or even more clearly: “There is no adequate reason for a fall in profit but a rise in wages, and…it may be added the only adequate and permanent cause for the rise of wages is the increasing difficulty of providing food and necessities” (Chapter XXI, p. 197).
Note that the increase in the wage comes either from an improvement in (what we now call) real wage or from greater cost of providing subsistence which, while keeping real wage unchanged, raises the share that belongs to labor, and reduces that of capital. Throughout are not only the interests of workers and capitalists directly opposed but workers are supposed to be paid subsistence, and when, in very unusual circumstances, they are not, the Malthusian checks kick in to drive them back to subsistence (Chapter V).
In Marx, the opposition between workers and capitalists is similar but the distinction between simple and complex labor introduces some variability among workers’ wages even if Marx seldom speaks of it. In fact, workers with greater skills will earn more. The rationale is very similar to “human capital” approach. In principle, workers are paid the amount necessary for the reproduction of their class. That could be subsistence only for unskilled workers who are plentiful; for skilled workers the costs of reproduction may be above subsistence because it costs more to produce a skilled than an unskilled worker: “[the difference in wages] can be reduced to the different values of labour-power itself, that is, its varying production costs” (Theories of Surplus Value; also Rosdolsky, pp. 515ff); or “all labor of a higher or more complicated character than average labor is…labor power whose production has cost more labor and time and which therefore has a higher value than unskiled or simple labor” (Capital, vol. I, Chapter III. Section 7). In contemporary terms we could say that the skilled wage must compensate for the foregone earnings during the period of training and for the cost of additional education.
Income inequality among workers thus moves us a bit further from a narrow functional distribution of income. If in addition, we allow for the differentiation of capital stock among capitalists which is implicitly present in both Ricardo and Marx, within-capitalist income Gini will be positive too.
The situation present in today’s capitalism but not common in classical capitalism, namely that (i) a worker may be richer than a capitalist, or (ii) that people could have both labor and property incomes (even if the rich still depend mostly on property incomes), is not envisaged by either Ricardo or Marx. They must have thought both of these possibilities remote and thus not worth complicating the analysis. Possibility (i) existed as some (few?) members of liberal or scientific professions, say doctors or engineers, probably commanded higher incomes than petty capitalists. Possibility (ii) existed only among the self-employed but they could rightly be considered remnants of a past social order and not representative of capitalism. The British social tables, whether in their original form or as they had been reworked by Peter Lindert and Jeffrey Williamson, or more recently by Bob Allen, can be read as the rankings of different non-overlapping classes where the lion’s share of inequality is explained by income gaps between these classes. In other words, we do not lose much in our estimate of total inequality if we ignore both the overlap component, and assume all members of a given class to have same incomes.
It was thus left to people like Pareto, who were, at the end of the 19th century, witnessing less segregated and less hierarchical societies and were lucky to have access to tax data, to move the study of inequality from functional to interpersonal.
David Ricardo, The Principles of Political Economy and Taxation, Dover Publication, 2004.
Roman Rosdolsky, The Making of Marx’s ‘Capital’, Pluto Press, 1977.