“Scripts, Plans, Goals and Understanding: An Inquiry Into Human Knowledge Structures” was written by Roger C. Schank and Robert P. Abelson and published by Lawrence Erlbaum Associates in 1977. The full text is preserved by the Internet Archive. The book asks what knowledge a person, or a program, must already have in order to understand even a simple story, and answers that understanding depends heavily on prepackaged structures of expectation rather than on logic applied from scratch.
The book’s signature contribution is the script: a stereotyped sequence of events for a familiar situation. The often-cited example is the restaurant script, which encodes that you enter, are seated, read a menu, order, eat, pay, and leave. Armed with that script, a program reading “John went to a restaurant. He left a large tip.” can infer the unstated middle, that John ordered, ate, and was served well, because the script fills the gaps. Above scripts the authors layer plans, which capture how an actor pursues a goal when no ready-made script applies, and goals and themes, which explain why characters act. The whole apparatus builds on Schank’s earlier Conceptual Dependency theory, in which sentence meaning is reduced to a small set of primitive acts.
These ideas drove a generation of story-understanding programs at Yale, including SAM and others, and they shaped how researchers thought about default knowledge, inference, and the role of expectation in comprehension. The notion that understanding language requires large stores of common-sense world knowledge, not just grammar, remains influential.
Why a business reader should care: every chatbot or document-understanding system that must “read between the lines” is grappling with the problem Schank and Abelson named, and their scripts are an early, intuitive model of the background knowledge that makes such inference possible.