The Doxification of Practical Reasoning

Abstract

In the previous chapters, we have viewed practical reasoning as being a procedure for acquiring (or abandoning) conative states: While theoretical reasoning consists in moving from one's current beliefs and perceptual states into new beliefs, practical reasoning consists in moving from one's beliefs and conative states into new conative states. We have also seen that practical reasoning can be as rational as theoretical reasoning can be. We shall now consider an important option that is available to an agent possessing both types of cognition. One can perform practical reasoning by using some of the resources one has for theoretical reasoning. This happens by refor-mulating conative states as if they were epistemic states, and in transferring into epistemic reasoning the reasoning schemata available for practical reasoning. We call this process the doxification of practical reasoning. 1 3.1. Doxification Consider, for example, the inference that leads us to adopt the intention of executing a plan, according to schema teleological inference. As we have seen above, when one (a) has a goal, and (b) believes that the plan is a satisfactory way of achieving the goal (the plan satisfies one's likings sufficiently well, and better than any alternative plan one has found through an adequate inquiry), then (c) one may adopt the intention to execute the plan. On the other hand, one abandons such an intention as soon as one believes that a better plan is available. The same result can also be obtained in an indirect way. One may ask oneself the apparently theoretical question "What plan is such that I should adopt it?," a question that may be viewed as an abbreviation for "What plan is such that I should have the intention of executing it?" In replying to this question, as we shall see, one will be led to recast one's conative states in the form of normative beliefs. 1 We take the basic idea of doxification from Pollock (1995, 277ff.), who speaks in this sense of doxastification: "Rather than requiring separate computational modules for defeasible epistemic reasoning and defeasible practical reasoning, human cognition makes do with a single module dedicated to epistemic reasoning and then integrates practical reasoning into that module using a technical trick. The trick involves 'doxastifying' normative judgement." We have reduced doxasti-fication to doxification just to provide a shorter term to express this idea.