Starting from general observations on form and substance, I take a closer look at knowledge representation and how this field has been treated in artificial intelligence (Al) research. I argue for directing more attention to the substance of knowledge and find similar views expressed in Lenat and Guha's Cyc project (Building Large Knowledge-Based Systems. Reading, MA: Addison-Wesley, 1989). Contrary to their view, however, I argue for not dismissing prior work like research concerning thesauri, and stress the importance of an interdisciplinary and intercultural approach in general. I also note some caveats and observations concerning the distinction between representing the world and its representation by means of language.