Frege über Merkmale von Begriffen

In this paper I want to show that two proposals to determine Frege’s notion of a mark (Merkmal) of concepts that are made in the relevant literature face some serious interpretative and systematic problems. The main problem of both conceptions is that they cannot be properly applied to those explicit examples of complex concepts that are given in Frege’s works. The first of these conceptions interprets marks as analytic components of a concept, the second as defining parts of a concept. I will show that only the second conception can be modified in a meaningful way such that we get a conception of marks as result that fits with Frege’s general characterizations and examples.