Friday, Nov. 13, 2009, 3:30 p.m., 607 Dale Hall Tower. Everyone is welcome!
Bolzano’s conception of what it is for an argument to be valid has been a popular topic in recent scholarship as well as in more general work on logical consequence. Most commentators however agree that Bolzano’s account of consequence falls through when it comes to capturing our intuitions about what it means for a conclusion to follow as a matter of logic from the premises. This is right. Nonetheless, the various criticisms often miss the fact that Bolzano’s views are both more complex and more attractive than one may assume at first glance. They are more complex since Bolzano’s views on logical consequence are doled out over not one but two distinct yet related aspects of his theory that are rarely presented as such: his conception of Ableitbarkeit and his conception of Abfolge. They are also more attractive, for just like Tarski’s views with which they are often compared Bolzano’s conceptions are neither trivial nor recklessly mistaken. In this paper I will present Bolzano’s views on Ableitbarkeit.