In 1969, Roger Schank of Stanford University introduced the model at the dawn of AI. Schank's pupils at Yale University, including Robert Wilensky, Wendy Lehnert, and Janet Kolodner, utilized this concept extensively.

Schank created the concept to represent knowledge for computers' natural language input. His goal, partially influenced by the work of Sydney Lamb, was to make the meaning independent of the words used in the input, such that two statements with the same purpose would have a single representation. The system was also designed to make logical deductions.

Objectives

• One, it can reveal the hidden meaning behind a sentence.
• Second, it facilitates the process of inferring meaning from text.
• Third, when two or more sentences convey the same meaning in different words. Only one interpretation of the meaning should be allowed.
• Finally, it offers representational tools that are not limited by any particular language.
• Fifth, it creates tools for translating between languages.

Rules

• Rule 1: It illustrates the relationship between an actor and the incident for which they are liable.
• Rule 2: It specifies the link that is asserted to exist between PP and PA.
• Rule 3: It describes the association of two PPs, one of which is a member of the set denoted by the other.
• Rule 4: It explains how a PP and a characteristic that is already based on it relate to one another.
• Rule 5: It explains the connection between two PPs, one of which gives the other a certain kind of information.
• Rule 6: It explains the connection between an ACT and the PP that serves as the ACT's object.
• Rule 7: It explains the connection between an ACT's source and recipient.
• Rule 8: It explains the connection between an ACT and the instrument used to accomplish it. This instrument must never be a single physical item; it must always be a whole idea.
• Rule 9: It explains how an ACT is related to its physical source and destination.
• Rule 10: It depicts the connection between a PP and the states in which it both began and concluded.
• Rule 11: It illustrates the causal relationship between two conceptualizations.
• Rule 12: It illustrates the connection between conceptualization and the moment the described event occurred.
• Rule 13: It discusses the timing of the first conception and the relationship between one and another.
• Rule 14: It explains the connection between conceptualization and the location where it took place.

Conclusion

Schank created the conceptual dependency theory to convey meaning. This method identifies a sentence's structure and meaning in a single step. CDs are very helpful when there isn't a specific rule for sentence structure.

Natural language processing relies on this representation to accurately portray the meaning of sentences to conclude the text. It makes no assumptions about the original language spoken by the speakers of the sentences. Conceptual "primitives," rather than actual language words, are used to construct CD representations of sentences; when put together, they convey the intended meanings of individual words.