Increasingly in recent years linguists have yielded to the persuasion that beneath the impressive surface diversity of the worldfs languages lies an innate species-specific capacity for language. Indeed, it can be said that the adoption of this perspective was prerequisite to the beginnings of an interest in linguistic theory, and that the latter consists chiefly in attempts to formulate a coherent system of hypotheses about the defining characteristics of the assumed human faculte* de langage. Thus, specific theoretical claims (as, for example, those inherent in the use of certain notational devices) are thought by their proponents to be isomorphic in some still poorly understood sense with properties of the neurophysiological mechanism which. gives rise to linguistic behavior. One of the most widely accepted bases for inferences about such properties is the evidence of what some linguists call language universals. Greenberg, Osgood and Jenkins (1963, Memorandum) recognize six types of synchronic language universals distinguished with respect to what they call'logical structure1.