I think of not wasting time on yak shaving as a sign of cognitive advancement, not cognitive decline! It's not that I can't shave yaks like I used to. It's that

I think of not wasting time on yak shaving as a sign of cognitive advancement, not cognitive decline! It's not that I can't shave yaks like I used to. It's that I realize that shaving yaks is a stupid waste of time that could be spent doing something productive or fun. Of course, if one enjoys shaving yaks, then by all means, shave away! But don't shave a yak just to prove that you can, and don't sneer at the people who don't - just because they don't shave your yak doesn't mean they can't. It means their priorities are different than yours.