Kant on the Act of Hypothesizing

The article explores Kant’s theory of hypotheses and their place in Kant’s system of holding-to-be-true (doxastic attitudes). A hypothesis is a provisional judgment, and the doxastic attitude corresponding to this act is defined by Kant “opinion” (Meinung). The article argues that hypotheses are provisional judgments that, qua probable opinions, are accompanied by a presumption of truth (Voraussetzung). A presumption is a provisional assent to a judgment until the opposite of the judgment is proven. Interpreting hypotheses as presumptions makes it explicit why for Kant hypotheses are neither object of persuasion, nor of conviction. Furthermore, it explains why hypotheses have a specific inquisitive function insofar as they arouse a focused inquisitive disposition. By providing a reconstruction of Kant’s account of hypotheses, we offer a basis to a new reconsideration of Kant’s position both in the history of philosophy of science and in Kantian scholarship. Our interpretation shows that the link between hypotheses and presumptions can be drawn based on an established tradition in early modern philosophy concerning legal presumptions.