Existence is reflected in natural language is not as a univocal notion, but divides into different modes of being, such as existence (as, roughly, endurance) and occurrence. One aim of the paper is to distinguish sharply between abstract artifacts and non-existent objects (e.g., plans vs. planned events that fail to occur); another is to argue for validity as a mode of being distinct from existence, as well as for corresponding distinctions among non-being.