The objective and the subjective in mid-nineteenth-century British probability theory

This paper provides a critical discussion of the historical and theoretical meaningfulness of the distinction between ‘objective’ and ‘subjective’ probability, as it supposedly emerged around 1840, by examining whether and how it appeared in the work of the mid-nineteenth-century British revisionist probabilists. A detailed analysis of the contributions of Augustus De Morgan, John Stuart Mill, George Boole, Robert Leslie Ellis and John Venn to probability is put forward in order to show that in so far as the terms did not appear as contradictories it is not possible to understand or compare these contributions with reference to the modern binary of ‘objective’ and ‘subjective’.