I am generally a fan of evolutionary psychology as an explanatory tool, though this doesn't sit well with me; it strikes me as a bit too reductionistic, and a bit too basic a model. Is the ultimate goal really to breed? Can we say that someone who has settled down in anonymous suburbia with a stable if dull job and started pumping out the children is more fulfilled than one who has found self-actualisation (through social, creative or otherwise constructive pursuits) but is childless? Are those who choose the latter path deluding themselves? It seems to say so.
Derek, having lots of offspring is the 'r' strategy, and only some organisms use it. Take flies: millions of babies but on average only one lives. The alternative is 'K' - having fewer offspring and investing more resources in each. In fact, each organism tries to maximize surviving offspring by choosing a strategy somewhere between extreme r and extreme K inclusive. See http://en.wikipedia.org/wiki/R/K_selection_theory
Even having zero offspring can be adaptive, if your genes survive through your investment in the offspring of close relatives. There are extreme examples of this, such as worker bees. This is the principle of inclusive fitness, see http://en.wikipedia.org/wiki/Inclusive_fitness. I've read speculation that in large human families, one offspring will typically choose a zero-offspring strategy that confers higher status on the siblings (eg priesthood, indie, depending on the era), thus producing relatively more copies of one's DNA via nieces and nephews.
The danger in speculating whether one ought to 'break the rules' of one's evolved psychology, is that the machine one is using to calculate the answer is an evolved psychology! One therefore can't know whether one is unwittingly kidding oneself.
Perhaps we're programmed to ask that question? After all, we only have three choices: lots of kids, a small number of kids, or no kids, seeking social status instead. These are all fitness-maximizing strategies, as the references above show.
So we might think we're choosing something like "evolutionary robot" vs "free mind", but in fact simply be figuring out which fitness-maximizing strategy fits our particular life circumstances.
Yeah, it sounds like an over-simplified way of thinking about evolution. Like, if you think of evolution in a "first order" sense, then the goal should be to pump out as many babies as fast as possible. However that's not usually the best strategy for survival. (Unless you're an insect or something.)