The following Bayesian confirmation measure is associated with John Maynard Keynes, having appeared in his A Treatise on Probability (1921). The degree to which evidence e confirms hypothesis h is given as:
Interestingly, this is strongly reminiscent of a subsequent measure found in Shannon information theory. In philosophy literature, this formula can be found in Dretske’s formulation of information transmission derived from Shannon’s work as well as a measure of transmitted information given by Hintikka.