Psychologists who study moral reasoning know this is how we make most judgments of right or wrong. We have a gut response, and we only look to logic if we are forced to explain our feelings. Many times, we can’t even come up with a logical reason to defend our judgment — but we stick with our feelings anyway.
Take, for example, one of the morally dubious scenarios psychologists use to study how we decide what is right and what is wrong.
Do you think it is morally acceptable for an adult brother and sister to have sex, if they both want to and they use birth control?
For most of us, this question triggers an instant inner ick. That’s just wrong. Then we strain our brains to explain why it must be immoral. If we don’t get an inner ick, a sharp pang of guilt, or a twinge of anxiety when we think about something, it doesn’t feel wrong.
Returning to more mundane willpower challenges, if a behavior — like having another slice of birthday cake or putting one more little thing on our credit cards — doesn’t trigger that instinctive feeling of “wrongness,” we don’t tend to question our impulses. This is how feeling good about ourselves for past good behavior helps us justify future indulgences. When you feel like a saint, the idea of self-indulgence doesn’t feel wrong. It feels right. Like you earned it. And if the only thing motivating your self-control is the desire to be a good enough person, you’re going to give in whenever you’re already feeling good about yourself.
— The Willpower Instinct (Kelly McGonigal), Loc. 1324–34