Deductivists deem ampliative reasoning invalid. If most reasoning is ampliative, then deductivists deem most reasoning invalid. That unpleasant consequence may seem reason enough to reject deductivism. To be sure, logic has a critical function. The task of the logician is not just to describe or ‘model’ how people do in fact reason, but also to prescribe how people ought to reason if they are to reason well. But if most reasoning is ampliative, then deductivists seem committed to the view that most of the time we do not reason well. Deductivism is a utopian ethic according to which most ordinary logical behaviour is thoroughly immoral!

Alan Musgrave, “Popper and Hypothetico-Deductivism”