> most professional activity, such as entrepreneurship, scientific or career advancement occurs in that period of life entrepreneurship and scientific advancem

> most professional activity, such as entrepreneurship, scientific or career advancement occurs in that period of life entrepreneurship and scientific advancement? Meh. Lots of evidence there are sweet spots for that well into your 50s and beyond. Would you rather work an extra decade but live healthily into your 80s or 90s - or try to cram it all in so you can retire unhealthy and miserable in your 50s with your life cut short and dying before you reach 70? I know that's not always the exact trade-off, but I'd rather get my full eight in every night and work productively into my 60s as a healthy person. The idea that work and relaxation are two extreme, distinct periods of life makes sense for a coal miner, but most of us here, fortunately, as "knowledge workers," have the luxury to weave the two together until we get dementia.