Probability in Philosophy and Science

Probabilities permeate all aspects of our lives. The beliefs we form, the various risks we assess, the epistemic uncertainty we account for, and the decisions we make typically depend on how likely we take some relevant states of the world to be. As finite subjects living in a vast world, we are constantly facing various forms of uncertainty, and it is our experiences that provide us with our most direct, though still limited, access to the world. Given the limited and perspectival character of our fundamental justifiers, i.e. our experiences, our beliefs (and the justification we have for them) seem to come in degrees. Many identify such degrees of belief, or credences, with subjective probabilities.

On the other hand, it seems that probability can be interpreted in a more objective way as well. One’s subjective probability assignments may be internally consistent and yet strike us as objectively unjustified or inadequate. Accordingly, some aim to account for probability in epistemic terms that are less subjective than belief, linking it to evidence or justification. Finally, and perhaps most widely assumed, there is the view that probability is a feature of the world itself: probabilities are completely independent from any subject but are out there in the world. This view seems to align well with certain branches of science such as statistics or quantum mechanics. Of course, we can also be pluralists about probability, allowing for both subjective and objective forms of probabilities.

However, despite this widespread and apparently intuitive distinction, the details of this overall picture still remain widely debated. What is more, the role probability plays in science remains strongly contested. For instance, quantum mechanics is one of the most fundamental scientific theories, but it is far from clear how we are supposed to interpret quantum probabilities. For some, they are prime examples of objective probabilities; others advocate a thoroughly subjective interpretation. On top of that, various researchers working on reconstructing quantum theory from information-theoretic principles have come to the conclusion that quantum theory fundamentally is a theory of probability.

This conference has three interrelated aims: to 1) interrogate the nature and epistemological implications of probability, 2) address the role of probability in science, and 3) assess the epistemic, formal, and pragmatic norms governing our probability assignments.

Issues we wish to discuss include, but are not limited to:

- the nature of probability;

- pluralism about probability;

- the relation between probability and concepts such as belief, experience, and justification;

- the constraints on rational probability assignments;

- the relation between probability and reality;

- phenomenological approaches to probability;

- the place of probability in action;

- the role that probabilities play in the sciences;

- the interpretation of quantum probabilities.