Mon 22 Mar 2010
Where do We Begin?
Posted by Susan Krantz Gabriel under Philosophy Department Blog , Susan Krantz Gabriel , Weekly Word[3] Comments
Years ago, somebody asked me whether it makes a difference philosophically if you begin with objective starting points (as Aristotle does) or subjective ones (as Descartes does). At the time my answer was that you could go either way; the big questions can be answered from either perspective, and the answers will be similar, although admittedly the details will differ. For instance, the individual man or ox is a given for Aristotle, while for Descartes it is arrived at only by an inference the ultimate first premise of which would be “I think, therefore I am.” Subjective starting points may give you a more complicated account in many (not all) cases, I thought, but there was no reason to think the account inadequate.
However, it seems to me now that there is a clear priority of one set of starting points over the other. Let me illustrate with an argument from Bertrand Russell’s Problems of Philosophy (PPh) in which he shows that the coherence theory of truth presupposes the correspondence theory. His question is how truth should be defined, whether as the correspondence between a belief and the facts, or as coherence among beliefs held. And he structures his answer around two main points. The first is that there may easily be more than one set of coherent beliefs about a given scientific or philosophical question, that is, there may be more than one hypothesis that is entirely coherent considered in itself. So coherence alone would not pick out the true hypothesis. The second point, and the more important one, is that coherence as a concept presupposes the truth of the principle of contradiction. The principle of contradiction, in turn, though it is what Russell calls a “Law of Thought” (PPh, chap. VII) must be understood to be, “about things and not merely about thoughts.” (PPh, chap. VIII) Thus the law of contradiction, being about things, if true presupposes a correspondence theory of truth. But if the principle of contradiction were false, then there could be no coherence of beliefs, i.e., no difference between coherence and incoherence. Therefore the concept of coherence presupposes the law of contradiction, but the law of contradiction presupposes the correspondence theory of truth. Therefore the concept of coherence presupposes the correspondence theory of truth. Coherence, Russell concludes, may be a test of truth, but cannot provide the definition of truth. (PPh, chap. XII)
By analogy, I think it fair to say that a philosophy based on subjective starting points presupposes a philosophy based on objective starting points. To that extent, the objectively-based philosophy is prior to, more easily known than, and logically required by the subjectively-based philosophy.
Here’s my argument: philosophies based on subjective starting points, such as Descartes’ cogito and the phenomenological method (in which the external world is “bracketed”) choose subjective starting points as foundations of knowledge. These foundations, in turn, are thought to be certain or evident in themselves and to impart reliability to beliefs that are based on the foundational beliefs. Typically this means that sensory knowledge of the external world, so called, cannot be foundational because of its susceptibility to error. Rather, sensory knowledge of the external world has to be derivative, or based on the subjective foundations. (Thus Russell tells that we have knowledge “by description” of the real table; only the appearances of the table—our sense-data—are known to us “by acquaintance.”) However, if there were no reliable sensory knowledge of external things (the individual man or ox), then there could be no knowledge that errors can infect our sense-perception-based beliefs about the external world. In other words, knowledge of the errors that can infect our sense-perception-based beliefs about the external world presupposes reliable sensory knowledge of external things. Otherwise one could never know that one had made a mistake (about the individual man or ox). But the philosophical program beginning with subjective starting points, such as Descartes’ cogito, presupposes knowledge of the errors that can infect our sense-perception-based beliefs about the external world. Therefore the philosophical program beginning with subjective starting points presupposes reliable sensory knowledge of external things. And therefore the objectively-based philosophy is prior to, more easily known than, and logically required by the subjectively-based philosophy.
In less abstract terms, this means that the philosophies of Descartes, Kant, Brentano, the phenomenologists, etc., and even Bertrand Russell in his reliance on sense-data (despite his defense of the correspondence theory of truth) are all logically dependent upon philosophies like those of Aristotle, Thomas Aquinas, and Thomas Reid. One can philosophize successfully in the subjective mode, no doubt, as Pope John Paul II has claimed with reference to phenomenology, which he considered complementary to, and a needed completion of, traditional or perennial philosophy. (Woytyla, “The Degrees of Being from the Point of View of the Phenomenology of Action, Analecta Husserliana, Vol. XI, 125-130.) But in doing so one must acknowledge a debt to those whose procedure is more empirical, that is to say, more direct.
The ultimate reason for this is that the human mind is by nature oriented to the knowledge of physical things, that is to say, it knows physical things first and most easily and knows its own activity (as in “I think, therefore I am”) not first and most easily but rather later and with greater difficulty. As Aquinas puts it, the human intellect, “. . .is not its own act of understanding [as God is], nor is its own essence the first object of its act of understanding [as in the case of angels], for this object is [rather] the nature of a material thing. And therefore that which is first known by the human intellect is an object of this kind, and that which is known secondarily is the act by which that object is known; and through the act the intellect itself is known, whose perfection is the act itself of understanding. For this reason did the Philosopher [Aristotle] assert that objects are known before acts, and acts before powers.” (ST, I, q.87, a.4)
Tags: Aristotle, Bertrand Russell, Descartes, Starting Points, Thomas Aquinas, Thomas Reid