How do we defend the rather outrageous statement, "You're evaluating your opportunity costs during every waking moment"?

We do it by reminding you that, even as you read these words, you're probably wondering if you should keep reading or do something else; that's an opportunity cost question.

When it's time for your next class you may wonder briefly if you can afford to ditch it. Should you go out with friends tonight or study? Should you go to a movie that appeals to you from the previews, but that your friends hated?

Should you major in a field that your parents suggested, like business, or one that you'll enjoy more, like film or creative writing?