a simple model of generative grammar discussed by Noam Chomsky in his Syntactic Structures (1957). In this model, it is supposed that the grammar generates sentences one unit at a time in strict linear sequence (i.e., working from left to right); once the first unit has been selected, the choice of subsequent units will be circumscribed at each stage by the sum of the previous choices. Chomsky presented this model, with its obvious inadequacy as an account of sentence generation, to demonstrate the need for the more complex explanations provided by phrase-structure grammar and especially by transformational generative grammar. Psychological interest in finite-state grammar stems largely from its similarity to certain principles of behaviorism and operationalism.