Fallible Rationalism And Machine Translation

Approaches to MT have been heavily influenced by changing trends in the philosophy of language and mind. Because of the artificial hiatus which followed the publication of the ALPAC Report, MT research in the 197Os and early 198Os has had to catch up with major developments that have occurred in linguistic and philosophical thinking; currently, MT seems to be uncritically loyal to a paradigm of thought about language which is rapidly losing most of its adherents in departments of linguistics and philosophy. I argue, both in theoretical terms and by reference to empirical research on a particular translation problem, that the Popperian "fallible rationalist" view of mental processes which is winning acceptance as a more sophisticated alternative to Chomskyan "deterministic rationalism" should lead MT researchers to redefine their goals and to adopt certain currently-neglected techniques in trying to achieve those goals. I. Since the Second World War, three rival views of the nature of the human mind have competed for the allegiance of philosophically-minded people. Each of these views has implications for our understanding of language. The 195Os and early 1960s were dominated by s behaviourist approach tracing its ancestry to John Locke and represented recently e.g. by Leonard Bloomfield and B.F. Skinner. On this view, "mind" is merely a name for a set of associations that have been established during a person's life between external stimuli and behavioural responses. The meaning of a sentence is to be understood not as the effect it has on an unobservable internal model of reality but as the behaviour it evokes in the hearer. During the 1960s this view lost ground to the rationalist ideas of Noam Chomsky, working in an intellectual tradition founded by Plato and reinaugurated in modern times by Hone Descartes. On this view, stimuli and responses are linked only indirectly, via an immensely complex cognitive mechanism having J ts own fixed principles of operation which are independent of experience. A given behaviour is a response to an internal mental event which is determined as the resultant of the initial state of the mental apparatus together with the entire history of inputs to it. The meaning of a sentence must be explained in terms of the unseen responses it evokes in the cognitive apparatus, which might take the form of successive modifications of an internal model of reality that could be described as "inferencing". Chomskyan rationalism is undoubtedly more satisfactory as an account of human cognition than Skinnerian behaviourism. By the late 197Os, however, the mechanical determinism that is part of Chomsky's view of mind appeared increasingly unrealistic to many writers. There is little empirical support, for instance, for the Chomskyan assumptions that the child's acquisition of his first language, or the adult's comprehension of a given utterance, are processes that reach well-defined terminations after a given period of mental processing -language seems typically to work in a more "open-ended" fashion than that. Within linguistics, as documented e.g. by Moore ~ Carling (1982), the ChomsMyan paradi~ is hy now widely