 For example, for even very simple pairs of propositions (such as ‘This is red’ and ‘That is blue’), where one might have expected objective relations to be more readily accessible, there is very little agreement as to what probability relation might connect them. Ramsey also notes that, while most people will agree that the probability of a fair coin landing heads is \(\frac{1}{2}\), ‘we can none of us say exactly what is the evidence which forms the other term for the probability relation about which we are then judging’ (1926a, [FM] 162).