A Reconstruction of Bertrand Russell’s Argument on How A Priori Knowledge is Possible (original) (raw)

THE IDEA OF A PRIORI REVISITED

In this article I would like to discuss the concept of a priori mainly focusing on Kant's Copernican revolution. How is metaphysics at all possible and how a priority takes place in Kantian metaphysics are the questions that I have addressed in the first part of my article. In this context, I have explained analytic, synthetic distinction from epistemological, metaphysical and semantical perspectives and I want to show how the concept of a priori and other associated notions are derived from this different perspective.

Cambridge Philosophers IX: Bertrand Russell

Philosophy, 1999

This paper attempts to summarise the philosophical career of Bertrand Russell, concentrating in particular on his contributions to logic and the philosophy of mathematics. It takes as its starting point Russell's conception of philosophy as the search for foundations upon which certain knowledge might be built, a search which Russell, at the end of his career, declared to be fruitless. In pursuing this search, however, Russell was led to develop lines of thought and techniques of analysis that have had a profound and lasting influence on the philosophy of the twentieth century.

Kant ; : Synthetic A Priori Judgments

The Critical Philosophy Next we turn to the philosophy of Immanuel Kant, a watershed figure who forever altered the course of philosophical thinking in the Western tradition. Long after his thorough indoctrination into the quasi-scholastic German appreciation of the metaphysical systems of Leibniz and Wolff, Kant said, it was a careful reading of David Hume that "interrupted my dogmatic slumbers and gave my investigations in the field of speculative philosophy a quite new direction." Having appreciated the full force of such skeptical arguments, Kant supposed that the only adequate response would be a "Copernican Revolution" in philosophy, a recognition that the appearance of the external world depends in some measure upon the position and movement of its observers. This central idea became the basis for his lifelong project of developing a critical philosophy that could withstand them. Kant's aim was to move beyond the traditional dichotomy between rationalism and empiricism. The rationalists had tried to show that we can understand the world by careful use of reason; this guarantees the indubitability of our knowledge but leaves serious questions about its practical content. The empiricists, on the other hand, had argued that all of our knowledge must be firmly grounded in experience; practical content is thus secured, but it turns out that we can be certain of very little. Both approaches have failed, Kant supposed, because both are premised on the same mistaken assumption. Progress in philosophy, according to Kant, requires that we frame the epistemological problem in an entirely different way. The crucial question is not how we can bring ourselves to understand the world, but how the world comes to be understood by us. Instead of trying, by reason or experience, to make our concepts match the nature of objects, Kant held, we must allow the structure of our concepts shape our experience of objects. This is the purpose of Kant's Critique of Pure Reason (1781, 1787): to show how reason determines the conditions under which experience and knowledge are possible. Varieties of Judgment In the Prolegomena to any Future Metaphysic (1783) Kant presented the central themes of the first Critique in a somewhat different manner, starting from instances in which we do appear to have achieved knowledge and asking under what conditions each case becomes possible. So he began by carefully drawing a pair of crucial distinctions among the judgments we do actually make. The first distinction separates a priori from a posteriori judgments by reference to the origin of our knowledge of them. A priori judgments are based upon reason alone, independently of all sensory experience, and therefore apply with strict universality. A posteriori judgments, on the other hand, must be grounded upon experience and are consequently limited and uncertain in their application to specific cases. Thus, this distinction also marks the difference traditionally noted in logic between necessary and contingent truths. But Kant also made a less familiar distinction between analytic and synthetic judgments, according to the information conveyed as their content. Analytic judgments are those whose predicates are wholly contained in their subjects; since they add nothing to our concept of the subject, such judgments are purely explicative and can be deduced from the principle of non-contradiction. Synthetic judgments, on the other hand, are those whose predicates are wholly distinct from their subjects, to which they must be shown to relate because of some real connection external to the concepts themselves. Hence, synthetic judgments are genuinely informative but require justification by reference to some outside principle. Kant supposed that previous philosophers had failed to differentiate properly between these two distinctions. Both Leibniz and Hume had made just one distinction, between matters of fact based on sensory experience and the uninformative truths of pure reason. In fact, Kant held, the two distinctions are not entirely coextensive; we need at least to consider all four of their logically possible combinations: Analytic a posteriori judgments cannot arise, since there is never any need to appeal to experience in support of a purely explicative assertion. Synthetic a posteriori judgments are the relatively uncontroversial matters of fact we come to know by means of our sensory experience (though Wolff had tried to derive even these from the principle of contradiction). Analytic a priori judgments, everyone agrees, include all merely logical truths and straightforward matters of definition; they are necessarily true.