Marianne answers questions from the audience about the four talks in this series.

In the fourth and final lecture, we examine the notion of ‘objective fact’ on which scientific theories are built; what sort of fact is such that we can build a scientific theory on it?

In the third lecture we examine first the so-called “Gettier Problems” for the traditional account of knowledge, the arguments for saying that possible worlds exist and finally we ask whether there really are unactualised possibles.