In order to shed light on contemporary arguments about “fine-tuning” in cosmology, I examine a possible historical precedent for fine-tuning from the early years of Quantum Electrodynamics: the divergent self-energy of the electron in Dirac's theory. I argue that viewing this problem as a fine-tuning problem involves an anachronistic reconstruction, but that such reconstructions can be philosophically useful so long as they are not confused with real historical understanding. I relate how, historically, this problem really was conceived, and show how one important step toward its solution drew upon an interpretation of Dirac's formalism in terms of “hole theory.” In light of the subsequent demise of hole theory, I argue that my anachronistic reconstruction can serve as a cautionary tale that should considerably weaken the conclusions that might otherwise be drawn from attempts to give theistic or multi-verse solutions to cosmological fine-tuning problems.

Peter Galison has recently claimed that twentieth-century microphysics has been pursued by two distinct experimental traditions—the image tradition and the logic tradition—that have only recently merged into a hybrid tradition. According to Galison, the two traditions employ fundamentally different forms of experimental argument, with the logic tradition using statistical arguments, while the image tradition strives for non-statistical demonstrations based on compelling (“golden”) single events. I show that discoveries in both traditions have employed the same statistical form of argument, even when basing discovery claims on single, golden events. Where Galison sees an epistemic divide between two communities that can only be bridged by a creole- or pidgin-like “interlanguage”, there is in fact a shared commitment to a statistical form of experimental argument.