I'm not a fan of new year's resolutions that tend (in my experience) to have limited impact and are often soon forgotten. My cynical self says the same thing applies to pledges, vows and other stated commitments, even agreements and contracts to some extent. They are more symbolic than actual control mechanisms (although I'm sure the lawyers would argue otherwise - on the clock, naturally). The focus is often on avoiding, preventing or stopping bad things, a negative emphasis although the actual language may be positive as in "I will lose weight" and "I will get fit". They can be a last resort, a sharp retrospective reminder of where we thought we were going when we are already heading off-course.