[declan]

>What precisely is it about having a child and having a mortgage that qualifies someone as "grown-up"?

It's shorthand for assuming adult responsibilities. It's difficult to survive on your emotionally fulfilling but minimum wage job if you have a brood in diapers at home. Obviously you still have responsibilities, probably including property taxes, insurance, and utilities, if you own your house outright as opposed to having a mortgage.

BTW, it's a bit tricky to buy your home outright if you live, in, say Palo Alto, where I recall a bunch of YC-funded startups are based:

http://www.paloaltoonline.com/news/2013/12/24/real-estate-ma... "In Palo Alto the median sales price for a home was $2.2 million..."

[nileshtrivedi]

I understand that IF you have a spouse or kids, it's your responsibility to take care of them and provide the best possible environment for them to flourish.

But it does not follow that it's one's responsibility to marry and have kids. There have been plenty of people who contributed a lot to society without ever marrying or raising kids.

You're right that managing a family is shorthand for being responsible. My point is: why use a shorthand when you can simply ask "So what are you doing with all the extra time you get because of not having a family?".

Ask, don't presume.

(I am not even getting into the whole philosophical debate of whether "work == virtue". The subtext in comments like the above is: "Oh, you're living a comfortable life with no responsibilities? You should work hard and suffer like the rest of us!" )

[wtbob]

> But it does not follow that it's one's responsibility to marry and have kids. There have been plenty of people who contributed a lot to society without ever marrying or raising kids.

One's responsibility is to do the right thing, to do one's duty. For some folks, that duty has not been to form a family, but for the vast majority of folks their duty has been to do exactly that: to repay their ancestors' millions of years of evolutionary investment by investing in their descendants.

There are some folks who have repaid that rather massive debt in other ways, but they are few and far between; far more these days simply renege on it.