Doing What is Best

If doing what is best sets the right ideal of rational agency, then rational agents should do what they believe to be best. As long as we leave open the question what makes an option best, all plausible theories of rationality willfit into this framework. Consequently, rational agents will always want to do the things they believes to be best. This claim is an instance of what David Lewis calls the desire-as-belief thesis, which he has tried to refute. I reject Lewis' argument by criticizing his treatment of belief-change in respect of propositions about degrees of goodness.     

Vann McGee's counterexample to modus ponens

Conclusion After rejecting some unjustified criticism of McGee's claim about modus ponens, I argued for two conditionals: If the Adams-Appiah theory of conditionals is correct, then modus ponens is saved from McGee's counterexample. If the Lewis-Jackson theory is correct, the same holds. Furthermore, I raised some doubts whether the antecedents of these conditionals are true. But, if one of them were, then, by modus ponens, modus ponens would be generally valid.     

Valuing Knowledge: A Deontological Approach

The fact that we ought to prefer what is comparatively more likely to be good, I argue, does, contrary to consequentialism, not rest on any evaluative facts. It is, in this sense, a deontological requirement. As such it is the basis of our valuing those things which are in accordance with it. We value acting (and believing) well, i.e. we value acting (and believing) as we ought to act (and to believe). In this way, despite the fact that our interest in justification depends on our interest in truth, we value believing with justification on non-instrumental grounds. A deontological understanding of justification, thus, solves the Value of Knowledge Problem.