[I]n practice it is the negative that’s used by the pros, those selected by evolution: chess grandmasters usually win by not losing; people become rich by not going bust (particularly when others do); religions are mostly about interdicts; the learning of life is about what to avoid.
And it is wonderful advice of course, always worth keeping in mind: sometimes the best way to learn is by cutting out the bad parts, rather than trying to add in new good ones. There is merit to both, of course – cutting out the bad and adding in the good. But maybe cutting out the bad ideas first is a, er, good idea?
Losing fat before adding muscle is one way to think about it.1