UNIVERSIDAD NACIONAL AUTÓNOMA DE MÉXICO INSTITUTO DE INVESTIGACIONES FILOSÓFICAS

ABSTRACT
A ‘no miracles’ argument is still prevalent in the scientific realism debate, even if a lot has changed since Putnam’s formulation of it, and even if the word ‘miracle’ is generally avoided. For example, realists think that if the most central ‘working’ parts of a scientific theory were not even approximately true (for any serious theory of ‘approximate truth’), then it would be incredibly unlikely (loosely speaking ‘miraculous’) for that theory to deliver successful novel predictions with ‘perfect’ quantitative accuracy (e.g. to several significant figures). But this is precisely what we do indeed find in the case of Sommerfeld’s prediction of the hydrogen fine structure spectral lines. This paper explores possible scientific realist responses to this dramatic historical challenge.