Colin Clark

Overview

Colin Grant Clark (2 November 1905, London – 4 September 1989, Brisbane) was a British-Australian economist and statistician who was one of the founders of national income accounting.[1][2] Working in the Cambridge of the 1930s — where John Maynard Keynes cited him in The General Theory — Clark helped pioneer the use of gross national product as the basis for studying and comparing whole economies; he is conventionally paired with Simon Kuznets (working in the United States) as a co-founder of the national-accounts framework that still underpins macroeconomic measurement.[1][2] His The Conditions of Economic Progress (1940) became a classic of development economics.[1] After 1953 he directed the University of Oxford's Institute of Agricultural Economics (to 1969), and his later career centred on agricultural economics, the economics of subsistence farming (with Margaret Haswell), and the economic consequences of population growth, where — as a Catholic convert who served on the Pope's Commission on Population (1964–66) — he opposed neo-Malthusian pessimism.[1][3]

The 25% Limit — Relevance to Georgism

Clark's connection to the Georgist literature is a single empirical claim about the ceiling on sustainable taxation. In "Public Finance and Changes in the Value of Money," The Economic Journal 55(220), December 1945, pp. 371–389, Clark argued that when the public sector's tax take rises above roughly 25% of net national product, inflationary pressure tends to follow.[4][5] He restated the argument in later free-market tracts, notably Taxmanship (Institute of Economic Affairs, 1964), which "argued that taxes levied above 25% of net national product at factor cost were a source of inflation."[1] The claim was pointedly anti-Keynesian: Clark held that fiscal expansion beyond that threshold eroded the real value of money rather than delivering costless demand management.[5]

This "25% limit" is what makes Clark a fixture in one strand of Georgist argument. In Public Revenue Without Taxation (1993), Ronald Burgess leans on Clark's finding to argue that conventional taxation is inherently self-limiting and ultimately unsustainable, and that collecting land rent for public revenue — the single tax — is the way to fund government without breaching the inflation ceiling.[6] The claim is cited on the wiki's single-tax and Ronald Burgess pages on that basis.

Two honesty notes on the claim itself (EDITORIAL claim-type B, empirical):

• The magnitude is Clark's empirical generalization, not a settled law. It was drawn from British and other Western budget data of the 1930s–40s and framed through the quantity theory of money; it is a contested mid-century finding, not a confirmed constant, and modern economies have at times sustained higher tax shares. It should be presented as "Clark argued," not as an established threshold.
• The base matters, and secondary summaries vary. Clark's own formulation is tax revenue as a share of net national product at factor cost. Some later summaries loosely restate it as "government's share of national income" exceeding 25% — a different base.[5] The wiki should use Clark's precise wording (tax revenue / NNP) and flag the government-spending paraphrase as a secondary gloss.

See Also

• Ronald Burgess — invokes Clark's 25% limit to argue conventional taxation is unsustainable
• Public Revenue Without Taxation — the book that leans on Clark's finding
• Single Tax — the policy Burgess defends within Clark's ceiling
• Ground Rent — the non-tax revenue source proposed as the alternative
• Land Value Tax — its modern policy form

Sources

1. George Peters, "Colin Clark (1905–89): Economist and Agricultural Economist," QEH Working Paper Series QEHWPS69, University of Oxford. qeh.ox.ac.uk (PDF) — used for Clark's role as a founder of national accounting (paired with Kuznets; cited in Keynes's General Theory), the Oxford Institute of Agricultural Economics directorship, his Catholicism and the Population Commission, and the exact Taxmanship (1964) wording of the 25%-of-NNP-at-factor-cost inflation argument.
2. "Colin Clark (economist)," Wikipedia. en.wikipedia.org — used for the birth/death dates and places, British-Australian nationality, and the pioneering use of GNP for national-economy comparison.
3. "Clark, Colin Grant (1905–1989)," Australian Dictionary of Biography. adb.anu.edu.au — used for the death place (Brisbane), the conversion to Catholicism, the agricultural-economics and population work, and his opposition to "big government."
4. Colin Clark, "Public Finance and Changes in the Value of Money," The Economic Journal 55(220), December 1945, pp. 371–389. academic.oup.com — the primary source and origin of the 25% argument (bibliographic details verified; article behind paywall).
5. Grokipedia / secondary summaries of Clark's 1945 argument (e.g. the Springer Great Economists chapter, "Colin Clark (1905–1989)," link.springer.com) — used for the article's anti-Keynesian thrust and to document the "government's share of national income" paraphrase that differs from Clark's own tax-revenue/NNP base.
6. Ronald Burgess, Public Revenue Without Taxation (London: Shepheard-Walwyn, 1993), Ch. 1, p. 2. book page — used for Burgess's reliance on Clark's 25% finding to argue that conventional taxation is self-limiting and that land-rent collection is the sustainable alternative.