 Carnap’s key idea is that we can investigate the intension that a subject associated with an expression by investigating the subject’s judgments about possible cases. To determine the intension of an expression such as ‘Pferd’ for a subject, we present the subject with descriptions of various logically possible cases, and we ask the subject whether he or she is willing to apply the term ‘Pferd’ to objects specified in these cases. If we do this for enough cases, then we can test all sorts of hypotheses about the intension of the expression. (Chalmers 2012, p. 204)