… is from page 6 of my colleague Dan Klein’s superb 1998 monograph 3 Libertarian Essays  (in this passage Dan uses the word “parentalist” to mean what is normally meant by “paternalist”); the specific essay from which this quotation is drawn is Dan’s 1992 essay in Inquiry, “Go Ahead and Let Him Try: A Plea for Egonomic Laissez-Faire”:
If regrettable behavior arises in isolated and identifiable ways, more or less uniformly across individuals, then a helping hand from the government may be just the thing. If regrettable impulses are pervasive and personal, and the ability to deal with them is an art that applies beyond specifics, an art that is learned and strengthened through exercise and a sense of autonomy, then the parentalist hand needs to show its restraint.
DBx: The essay by Dan of which this quoted passage is a part is one of the most profound challenges ever leveled at paternalism – be it nudge-advocating “libertarian paternalism” or outright “I-ordain-myself-to-care-for-you-better-than-you-care-for-you” paternalism. Dan here shows that if behavioral economists and psychologists are correct that ‘irrational’ behavior is quite common among humans, then the case for paternalism is weak rather than strong.