On Friday I wrote: [Imagine] a fountain of youth pill … [that had] to be … given to everyone over thirty … [and] required dosage doubled every decade [of age]. … Eventually we’d run out of money to pay for these pills; we’d have to say no to some people, and then they’d quickly die. And the longer we waited before admitting to ourselves that we couldn’t afford to give effective treatments to everyone, no matter what the cost, the worse it would be.