SNePS is a knowledge representation, reasoning, and acting (KRRA) system developed and maintained by Stuart C. Shapiro and colleagues at the State University of New York at Buffalo. SNePS is simultaneously a logic-based, frame-based, and network-based KRRA system. It uses an assertional model of knowledge, in that a SNePS knowledge base (KB) consists of a set of assertions (propositions) about various entities. Its intended model is of an intensional domain of mental entities---the entities conceived of by some agent, and the propositions believed by it. The intensionality is primarily accomplished by the absence of a built-in equality operator, since any two syntactically different terms might have slightly different Fregean senses.