The proper use of conceptual analysis in metaphysics

The third lesson highlighted modal illusions, particularly those to which David Lewis's modal realism succumbs. The starting point was an analysis of the main conceptual distinctions (conceivable and possible, necessary a posteriori ; contingent a priori), before turning to the question of whether or not thea priori should retain its place in the project of a metaphysical knowledge of nature. Elements of a well-understood method of conceptual analysis were identified: knowing how to count; practicing intuitions and thought experiments; making good use of modalities without modal realism. Several major problems for conceptual analysis were then presented, before showing how they can be circumvented and, even more so, how they can be exploited. In examining the scope and limits of conceptual analysis, the importance of the following points was highlighted: how much room is still left fora priori, and how much room is left for cognitive psychology. It was also clear that the project must take into account the distinction between the "aim of understanding" and the "aim of knowledge", and that it is equally necessary to determine the way in which we know something a priori , and the role we are prepared to give, on an epistemic level, to intuition on the one hand, and to folk psychology and a certain "cognitive core"(core cognition) on the other.