Plato's dialogue with Kratylos is, if not the beginning, at least the first climax of Western philosophy of language. In the area of tension between the question of whether linguistic meaning has a conventional or natural basis, fundamental basic concepts such as sentence truth, name function, ability to represent and semantic compositionality of linguistic units are discussed within the framework of an indicated ontological overall approach. The commentary opens up the "Kratylos" dialogue for today's readers and makes the argumentation and the line of thought understandable.