Some people think that we can separate narrowly semantic knowledge from world knowledge. This is the difference between the entries in a dictionary which give the meanings of words and the encyclopedia knowledge that constitutes our knowledge of facts. The prior sort of thing will have the essential details of, say, cats to explain ‘cat’. The latter sort of thing will include informatoin about the evolutionary history of cats, the sounds they make, their common status as pets, their fabled love of chasing mice, and other things. These bits of information are not essential to the meaning of ‘cat’, so the story goes. It seems like this line of thought presupposes a strong analytic-synthetic distinction. If we can sort of the difference between meaning-constituting and non-meaning-constituting bits of information, then we have a way of specifying what is true in virtue of meaning and what is true in virtue of fact. This is a dubious idea. The moral we should draw is that there is no sharp line between dictionary knowledge and encyclopedic knowledge. As Marconi puts it, there is no perfect or complete encyclopedic competence.