Living standards and incomes go up when people start believing everyone DESERVES to live in a better world. This isn't born out of a change of philosophy; instead, a new philosophy emerges naturally from people who, owing to slowly improving childrearing over time, are different/better than previous generations (Lawrence Stone and Lloyd DeMause’s thesis). People aren't homo economicus -- people ruled by staid but rational monetary concerns. Many wish them such, like to see them as such, but people lust, love, hate -- they ARE, more often than not, best understood as irrational--human. If you are the type to want to know just a few people but very well, and very lovingly, you will not feel the need to have bunches of kids -- and you cannot be prompted to have them. You'll have a few -- depression or no; despite some tumult, you and they will know real love; and they will be ones who'll make the world a better place.
Link: The Tyee