In the 1950s, Buchanan proposed an analysis of public debt and public finances that challenged the Keynesian orthodoxy. Buchanan's analysis was rooted in philosophical assumptions about the nature and the role of the state. In this paper, we show how Buchanan's early views on the state led him to the problem of public debt and shaped his approach. Emphasis is given to the influence of Chicago classical liberalism and of Knut Wicksell -aspects that have generally gone unappreciated in narratives on Buchanan and debt. We show that the preliminary works of Buchanan on public debt demonstrate the need for public choice logic rather than serve as an application of such thinking.