Accounting historiography has often paid attention to individuals for their pivotal roles in the development of accounting practice and thought; however, little is known about individuals using accounting outside the traditional professional domain. This study explores the use of accounting calculations by a non-professional accountant, the intellectual Melchiorre Peccenini, who advocated his utopian project of an Italian colony in Australia in a book published in Melbourne. By analysing his life and context, as well as his writings and use of calculations, the article reveals how accounting was embedded in the intellectual discourse of an individual and became an advocating device. With its results, this investigation contributes to the accounting biography tradition by extending its boundaries to include ordinary individuals who can provide new insights into accounting as a multi-purpose device.