Individual Preferences Are Subjective
I recommend this month's featured article at Econlib, "The Relentless Subjectivity of Value" by Max Borders. It's in the context of economics, but anyone who reads my work here will surely recognize something familiar and useful. My favorite excerpt:
Nudging assumes a universal standard of well-being that simply cannot exist. For example, is it really that great to live longer? If foregoing scotch and bacon allows me to increase my life expectancy from 88 to 90, is it worth it to me? Will any amount of information possessed by folks at the Department of Health and Human Services cause me to see the light? I doubt it. I value my nightcap more than I value three more years at Shady Oaks. And I don't want to hear "you'll thank me when you're 90" because, a) I'm not 90 and b) I may or may not enjoy the life of incontinence at Shady Oaks. Call me irrational, but if you do, you're simply substituting your preferences for mine. Time, context and perspective count for a lot. Of course, none of this is meant to argue that your preferences or mine can't be changed by either nudging or thoughtful advice. The point is that architecting choices means rigging the incentives in favor of another's preferences, with no objective standard of value.
Again, even if you don't care about the economics, it's an interesting essay worth your time.