Chris Tucker

This entry explains what the issue of weighing reasons is about and then discusses a number of theories concerning weighing reasons. The general issue concerns how reasons (or considerations or pros and cons) systematically interact to determine the normative status of some action, belief, or attitude. For example, it concerns how reasons determine whether an action is permissible, required, or what ought to be done. The general issue also concerns how reasons aggregate or themselves result from systematic interactions with the broader context. Along the way, the entry considers whether reasons can be incommensurable (e.g., be on a par); whether reasons have more than one weight value (e.g., justifying, requiring, and commending); the relation between reasons for and reasons against; conditions (enablers, disablers); modifiers (amplifiers, attenuators); exclusionary reasons; higher order evidence; what happens when, say, morality and epistemic rationality conflict; and so on.

The book develops, defends, and applies a "Dual Scale" model of weighing reasons to resolve various issues in ethics. It tells you everything you ever wanted to know about weighing reasons and probably a lot of stuff you didn't want to know too. It addresses, among other things, what the general issue of weighing reasons is; what it is to weigh reasons correctly; whether reasons have more than one weight value (e.g., justifying, requiring, and/or commending weight); whether weight values are context sensitive; how to tell what the weights of reasons are; how reasons for are related to reasons against; and how the weights of reasons aggregate. After addressing such issues, it explains a number of puzzling phenomena in ethics, such as the All or Nothing Problem, the normative significance of small improvements, and the intransitivity of the makes-it-permissible-to-act-against relation.

It may seem that epistemic and practical rationality weigh reasons differently, because ties in practical rationality tend to generate permissions and ties in epistemic rationality tend to generate a requirement to withhold judgment. I argue that epistemic and practical rationality weigh reasons in the same way, but they have different "default biases". Practical rationality is biased toward every option being permissible whereas epistemic rationality is biased toward withholding judgment's being required.

Phenomenal conservatism holds, roughly, that if it seems to S that P, then S has evidence for P. I argue for two main conclusions. The first is that phenomenal conservatism is better suited than is proper functionalism to explain how a particular type of religious belief formation can lead to non-inferentially justified religious beliefs. The second is that phenomenal conservatism makes evidence so easy to obtain that the truth of evidentialism would not be a significant obstacle to justified religious belief. A natural objection to phenomenal conservatism is that it makes evidence too easy to obtain, but I argue this objection is mistaken.