Suppose that your present drinking will cause yourself a future hangover. When you imagine yourself experiencing the hangover now, you don't consent to the idea of your having treated yourself that way. Are you consistent?
Suppose that your present drinking will cause yourself a future hangover. When you imagine yourself experiencing the hangover now, you don't consent to the idea of your having treated yourself that way. Are you consistent?
There are other consistency conditions besides the golden rule.
Suppose that your present drinking will cause yourself a future hangover. When you imagine yourself experiencing the hangover now, you don't consent to the idea of your having treated yourself that way. Are you consistent?
You violate an analogue of the golden rule called the "future-regard principle." With this, you imagine yourself, not in the place of another, but at a future moment of time in which you experience the consequences of your action. And you ask, "Do I now consent to the idea of my having treated myself this way in this situation?"
Practical rationality requires that we take into account future consequences of our actions. More crudely: "Don't do what you'll later regret."