The basic idea of this book is that to have a positive impact on “the world”, make the default choice the best choice. This includes automatic enrollment in 401ks, stocking cafeterias with healthy food, etc. That way, the path of least resistance is the one that leads to a longer, healthier life.
It’s true, we do a lot of things unthinkingly. And if our habits were healthier, so much the better.
Tangentially but amusingly, they point out that the Social Security Administration’s website is not available 24/7, but works government hours of Weekdays 5 AM – 1 AM, Saturday 5 AM – 11 PM, Sunday 8 AM – 11:30 PM.

auth=Thaler and Sunstein
sub=Improving Decisions About Health, Wealth, and Happiness