Page 61 - Encyclopedia of Philosophy of Language

The term 'rationalism' is standardly used in histories of philosophy to contrast with 'empiricism.' Ration- alists (from the Latin ratio 'reason') are said to main- tain that knowledge can be arrived at by reason alone, independently of the senses, while empiricists (Greek empeiria 'experience') take it that there can be no knowledge which is not ultimately derived from sen- sory inputs. The classification is perhaps most familiar in textbooks of seventeenth- and eighteenth-century philosophy, where the 'British empiricists,' Locke, Berkeley, and Hume, are routinely contrasted with the 'continental rationalists,' Descartes, Spinoza, and Leibniz. But this blunt and schematic contrast is in many respects misleading; the 'rationalist' Descartes, for example, insists on the vital importance of sensory observation in testing scientific theories, while the 'empiricist' Locke, though asserting that 'all our knowledge is founded in experience,' nonetheless stresses the crucial role played, in the development of knowledge, by the mind's own active faculties for combining, comparing, and abstracting from sensory data.
1. Innate Ideas
Despite its problems, the rationalist/empiricist dis- tinction does provide a useful focus for a number of central issues in the philosophy of language. The most important of these is the issue of'innateness'. Ration- alists like Descartes, following a tradition that goes back as far as Plato, maintained that the human mind at birth is already imprinted with certain innate 'ideas'—a term which covered both concepts (such as the concept of God or of triangularity) and also propositions or principles (such as the principle of noncontradiction in logic). This implies, in effect, that there is a kind of innate language—a language of thought—which all human beings are born knowing. The term 'knowing' is a slippery one in this context, since it is clear that young children, for example, do not possess any explicit awareness of principles like the law of noncontradiction; and this led Locke and others to dismiss the whole notion of innate ideas. To this innatists replied that the knowledge in question might be present implicitly; in a suggestive analogy used by Leibniz in his New Essays on Human Under- standing (ca. 1704), the human mind at birth is likened to a block of marble—not a uniform block indiffer- ently suited to receive any shape the sculptor may choose to impose on it, but one already veined in a certain pattern. In this metaphor, the blows of the sculptor's hammer are likened to sensory inputs: with- out them there could be no sculpture, just as without
sensory inputs there could be no knowledge. But though the hammer blows are necessary, the internal veining is also necessary to explain the final shape. And similarly, a crude empiricism that appeals to sen- sory input alone is insufficient to explain knowledge of certain fundamental and universal principles of logic and mathematics; an innate prestructuring of the human mind must also be invoked.
2. A Universal Language of Thought
There is some similarity between the issues addressed in these early debates and the linguistic controversy over Noam Chomsky's notion of a 'universal grammar.' Just as Chomsky argues that the mind must be endowed from birth with certain deep structural principles which enable the young child to learn any language on the basis of very meager and defective linguistic data, so the earlier 'rationalists' argued for the theory of innate ideas by citing human ability to perceive and acknowledge fundamental conceptual and logical truths, whose validity is recognized as extending far beyond those cases which have actually been perceived by the senses. In both cases, what makes the argument persuasive, or at the very least challenging, is its insistence on the need to explain the gap between the limited actual empirical input in early life and the richness and scope of the eventual abilities (whether logical or linguistic) which all human beings normally develop.
The idea of a universal language of human thought is a pervasive one in rationalist philosophy, and is not confined to discussions of the innateness question. In the seventeenth century, the notion is often connected with a belief in a divine creator who has illuminated our minds with (at least some of) the fundamental principles which govern the universe as a whole. In a famous pronouncement, Galileo declared in // Sag- giatore (1623) that 'The great book of the universe cannot be understood unless one can read the lan- guage in which it is written—the language of math- ematics.' Some years later, Descartes announced his revolutionary program for the mathematicization of physics in closely similar terms. The qualitative lan- guage of earlier scholastic philosophy was resolutely to be avoided; all scientific explanations were to be couched in quantitative terms. 'I recognize no matter in corporeal objects,' wrote Descartes, 'apart from what the geometers call quantity... i.e., that to which every kind of division, shape and motion is applicable' (Principles of Philosophy 1644). Part of what this new program involved was a rejection of the ordinary lan- guage of the senses, with its supposedly 'com-
Rationalism J. Cottingham
Rationalism
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