Philosophy is a very diverse field in which practitioners employ different dialectical and rhetorical techniques to advance their views and critique those of their opponents. But despite the heterogeneity, there seems to me to be a prevailing attitude towards the overarching method by which we choose philosophical theories among contemporary philosophers. We are all supposed to acknowledge that there are no knockdown arguments in philosophy. Philosophical theories are not the sorts of beasts that can be vanquished with a quick deductive argument, mostly because there is no set of rules that we can use to determine if a theory has been refuted. Any proposed set of rules will be open to challenge by those who doubt them, and there will be no obvious way to determine who wins that fight.
So, the process by which we compare and choose among philosophical theories cannot be guided by which theories can be refuted by knockdown arguments, but rather we seem to be engaged in a form of cost-benefit analysis when we do philosophy. We look at a theory and consider whether its overall value outweighs that of its competitors, and then we adopt that theory rather than the others. One way of spelling this process out is in terms of reflective equilibrium; we consider the parts of the theories we are comparing and the intuitions we have about the subject matter that the theories are about, and then we weigh those parts and intuitions against each other. Once we reach some sort of state of equilibrium among our intuitions and the parts that compose the theory we’re considering adopting, we can be justified in believing that theory.
Reflective equilibrium seems to be the metaphilosopher’s dream, since it avoids the problems that plague the knockdown argument approach to theory selection, and it makes room for some level of reasonable disagreement among practitioners, since not everybody has the same intuitions, and the intuitions shared among colleagues may vary in strength (in both intrapersonal and interpersonal senses). Unfortunately for me, I worry a lot about how reliable our methods are at getting us to the truth, and the process I crudely spelled out above does not strike me as satisfactory.
To be brief, my concern is that we have no clear way of determining the values of the things we are trading when we do a philosophical cost-benefit analysis. In other cases of cost-benefit analyses, it seems obvious to me that we can make satisfactory judgments in light of the values of the goods we’re trading. If I buy a candy bar at the store on my way to work, I can (at least on reflection) determine that certain considerations clearly count in favor of purchasing the candy bar and others clearly count against it. But when I weigh intuitions against parts of theories and parts of theories against each other, I begin to lose my grasp on what the exchange rate is. How do I know when to trade off an intuition that really impresses itself upon me for a theory with simpler parts? Exactly how intense must an intuition be before it becomes practically non-negotiable when doing a philosophical cost-benefit analysis? Questions like these throw me for a loop, especially when I’m in a metaphysical realist mood. Perhaps anti-realists will have an easier time coping with this, but those sorts of views never satisfied me, because there are parts of philosophy (like some areas in metaphysics) that never really struck me as open to a complete anti-realist analysis, so at least for me global anti-realism is off the table. At the moment, I’m completely puzzled.