I can understand not wanting kids. I can understand wanting kids. What I cannot understand is not knowing whether you want kids. Having kids and not having kids are not alike. Not even close. The choices are not remotely equivalent. How do you answer the question with “Eh. You know, whichever.” How do you not know?
Here is more explanation, and here is a follow-up post, both from my current favorite theorist of rational choice. From another direction, the newly unattached Jacqueline Passey is unsure where to live, yet she is sure about not wanting children.
I find it easier to be certain when comparing two similar items or courses of action. I am sure that I prefer the Beatles to The Rolling Stones. Both are British popular music groups from roughly the same period of time. It is tougher to rank Charlie Parker relative to Dvorak. I reluctantly opt for Parker.
Some uncertainty about children may stem from the difference between ex ante and ex post preferences. You’re very happy having the kid when he or she comes but you did not care about that particular kid "in advance." Some of the "uncertainty" therefore is faux; it represents a confusion about which perspective to report.
Then there is the margin. How many kids should you have? I doubt if anyone is, ex ante, certain about this, although a few people may pretend to be ("Three is the number for me."). But one extra kid is a huge, huge difference at the margin, especially if you are moving from one kid to two (or so I hear). So it must be allowed that we can be uncertain about very drastic changes in our lives.
Most fundamentally, are indeed many people uncertain about having kids? How might we define such uncertainty? Surely we cannot trust our self-deceiving subjects to report their true intentions. Medical issues and "finding a mate" issues aside, for most of us isn’t it "in the cards" whether we will have kids, no matter how much we hem and haw in advance? (What is the function of the feigned uncertainty? Does it make the later decision "easier to live with" if we first pretend to put up a fight? Do we create an illusion of autonomy to feel in control?) Would small changes in our lives lead to big changes in the outcome here? I wonder.
What is personal uncertainty anyway?
Most of all, I am uncertain what we have reason to be uncertain about.