Chomsky's Government and Binding theory is aptly characterized as a radical departure from pre-existing theories of the human capacity for acquiring knowledge of syntax. Since Chomsky, the main concern in the field had been to determine what kind of linguistic principles are genetically determined and how those principles of UG are parameterized. Some of the postulated UG principles follow the spirit of 'least effort' or economy in that they "legislate against 'superfluous elements' in representations and derivations". Syntactic derivations are not allowed to contain any superfluous derivational steps. Chomsky suggests in addition that correspondingly "there can be no superfluous symbols in representations". Since the introduction of Chomsky's Minimalist Program, the ban on superfluous elements (in derivations and in representations) has been applied also to the entire architecture of UG. The Strong Minimalist Thesis regarding syntax, phonology, and semantics might be encapsulated as computationally efficient satisfaction of natural interface conditions.