Reason, Feeling, and Decisionmaking

AdamF over at Mormon Matters posted an argument the other day defending the legitimacy of allowing "feelings" to play a major role in decisionmaking.  He argues,

Without emotions, we are literally not capable of making decisions. No amount of logical thinking, reasoning, or studying can lead to actual decisions without the influence of emotion: “Cut off from our feelings, the most banal decisions become impossible. A brain that can’t feel can’t make up its mind.”

I don't disagree with Adam's assessment, but I think he may be missing some important distinctions about the kinds of decisions in which feelings play a legitimate role, and the kinds of roles that feelings legitimately play.

One legitimate role that emotion can play in rational decisionmaking is in determining our individual preferences. For example, if I find cookie dough more pleasurable than chocolate chip, then the only rational thing for me to do when faced with a choice between them is to pick cookie dough. Without this sort of emotional valuation of alternatives, we would have no preferences and selection among alternative courses of action would be impossible.

However, choosing a course of action is a little different than the case of deciding what is true. Assuming that we all emotionally prefer truth to fiction, we will want to employ the most powerful and reliable truth-evaluation techniques available. Hard experience suggests that what we call “logic” and “the scientific method” are more reliable than emotional preference when it comes to assessing the truth or falsity of a proposition. For example, no matter how much I want to believe that there will be no consequences if I do nothing but sit around watching TV and eating popcorn every day, it just isn’t true.

Of course, the assumption that we all emotionally prefer truth to fiction probably isn’t true, either. There are some things many of us would just rather not know. In that case, it is perfectly rational to decide based on emotional preference and to avoid evidence or rational analysis that might potentially disconfirm the alternative one has chosen.