Weighing reasons

What is involved in weighing normative reasons against each other? One attractive answer is the following Simple Picture: a fact is a reason for action when it counts in its favor; this relation comes in different strengths or weights; the weights of the reasons for and against an action can be summed; the reasons for performing the action are sufficient when no other action is more strongly supported, overall; the reasons are decisive when it is most strongly supported; one ought to perform the action there is most reason to perform; rational deliberation is weighing reasons correctly; and acting rationally is doing what one has sufficient reasons to do. This chapter examines the adequacy of this picture, concluding that while in some respects it needs modification or correction, in others the jury is out.