I apologize if I was unclear, but I meant that your 20s are generally thought to be 'the best years of your life', and those are precisely the years many spend

I apologize if I was unclear, but I meant that your 20s are generally thought to be 'the best years of your life', and those are precisely the years many spend getting a PhD (thus spoiling the years). Many smokers knew the risks, yet that did not shield the tobacco companies from the prosecutorial ire of the states.