 Detailed accounts of logicist AI that fall under the agent-based scheme can be found in (Lenat 1983, Lenat &amp; Guha 1990, Nilsson 1991, Bringsjord &amp; Ferrucci  1998).[26].  The core idea is that an intelligent agent receives percepts from the external world in the form of formulae in some logical system (e.g., first-order logic), and infers, on the basis of these percepts and its knowledge base, what actions should be performed to secure the agent’s goals. (This is of course a barbaric simplification. Information from the external world is encoded in formulae, and transducers to accomplish this feat may be components of the agent.) 