Knowledge of the basic rules of logic is often thought to be distinctive, for it seems to be a case of non-inferential a priori knowledge. Many philosophers take its source to be different from those of other types of knowledge, such as knowledge of empirical facts. The most prominent account of knowledge of the basic rules of logic takes this source to be the understanding of logical expressions or concepts. On this account, what explains why such knowledge is distinctive is that it is grounded in semantic or conceptual understanding. However, I show that this cannot be the correct account of knowledge of the basic rules of logic, because it is open to Gettier-style counter-examples.