(Edited. Note this conversation is from 2005.)
With my coworkers. We're having a conversation about bonds and stocks.
Jordan: [explaining how raising interest rates depreciates the bond market]
Kevin: I'm very risk-averse.
Jordan: Would you ever lend someone money? Say they'd pay you interest. But there's a chance they could go bankrupt.
Nadim: Say I needed money.
Kevin: Well, I would lend you money, Nadim, because we're friends. But not for financial reasons. It'd be because helping my friends makes me happy, and that's the purpose of life -- happiness.
Jordan: [shocked that conversation has suddenly become so philosophical]
me: [delightedthat conversation has suddenly become so philosophical] But is happiness really the metric that you're trying to monetize? Let's say you could be ignorant and happy. Most people wouldn't choose that. They'd rather have more knowledge, even if it makes them less happy. So what is that elusive metric that we're really optimizing? ... Let's say you love someone, and then they die. You'll be really sad, but many people would prefer that to not having known the person, even if they would've been happier that way.
Kevin: You were happy before they died, so the integral over all time is still positive.
me: But maybe not as positive as if you'd spent that time doing something else that made you happier.
me: I'm happy we're discussing this. I think about this once a month or so, and I can never come up with the metric. It would make life so much easier, if you had one metric to optimize for.
Jordan: When slashdot introduced the karma rating, all the users began madly to try to make that number go up. So I can imagine if people had a life rating, they'd all work on making that number as high as possible.
Kevin: Instead of PageRank, we'll have LifeRank.
Nadim: [solemnly] I know what my metric is. It's money.
Nadim: No, I'm serious.
Jordan: [to me] So all that time you spent considering the metric and debating what it is, he already has it figured out!
Kevin: [laughing] And he doesn't even need to calculate it himself! Someone else computes it for him!
me: [to Nadim] But you don't go around buying fancy cars or clothes!
Nadim: I don't spend the money. I'm a miser. You know DuckTales? I identify with that character, who's-it, Scrooge MacDuck.