I just read this article about the felicific calculus of parenthood.

 The average happiness worldwide is 5.1 on a one out of ten scale; Americans are at 7.1. Arbitrarily deciding that one year of a 10 life is equivalent to two years of a 5 life, the cost per QALY of having a child for total utilitarians is $5500.

However, NICE’s threshold for cost effectiveness of a health intervention is about $30,000 (20,000 pounds) per QALY. Therefore, for total utilitarians, having a child may be considered a cost-effective intervention, although not an optimal intervention.

...surrogacy is an underexplored way to do good. Rather than costing money, the first-time surrogate earns thirty thousand dollars, which can grow to forty thousand dollars for experienced surrogates– and it still creates 109 QALYs that otherwise would not exist. These children are likely to grow up in wealthy families who really, really want to have them, and are thus likely to be even happier than this analysis suggests.

 In the comments section, the following grabbed my attention.

Estimates for the size of a sustainable human population appear to mostly range between 2 billion and 10 billion, and the meta-analysis here (http://bioscience.oxfordjournals.org/content/54/3/195) suggests that the best point estimate is around 7.7 billion. Meanwhile most estimates of population growth over the next hundred years suggest the total population will reach 10-11 billion. It seems likely that at some point in the next couple hundred years, the population will decrease substantially due to a Malthusian catastrophe. This transition is likely to cause a great deal of suffering. Surely even a total utilitarian would agree that it would be better for the necessary drop in population to be as small as possible.

And even if the population never rises above sustainable carrying capacity, it’s not obvious that total utilitarians should see a larger population as preferable. The drop in happiness due to increased competition for resources could outweigh the benefit of an additional person existing and having experiences.

Then, I read this article. Here are the highlights:

 

Bryan Caplan’s excellent book Selfish Reasons to Have More Kids[7] reviews the evidence from 40 years of adoption and twin studies with a frankly liberating result: *barring actual deprivation or trauma, children are largely who they are going to be as a result of their genetic makeup. In long-term measures of well-being, education and employment, parental influence exerts a temporary effect which disappears when we are no longer living with our parents. So costly added extras (music lessons, coaching and tutoring, private school fees) are probably not going to change your child’s life in the long term.  (However, data on the antenatal environment suggests benefit to taking iodine, but avoiding ice-storms and licorice during pregnancy.[8]) Sharing time together and finding common interests can build a good relationship and help a child develop without major costs.

In addition to straightforward financial outlay, parenthood comes with costs of time and opportunity. Loss of flexibility and leisure mean you won’t be able to take all opportunities (like taking on extra work to make more money or advance your career). Late notice travel is unlikely to be possible. You will probably be sleep deprived for a large part of the first year or more of your child’s life, and this may impact on your work performance. The work of parenting will take time, though some of it may be outsourced at the cost of increased financial outlay.

So, this baby is going to cost you about £2000 a year and take a variable but large amount of your time, which will equate in the end to another chunk of money. For parents taking parental leave or working less than full time to provide childcare, there may be delay to career progression as well as income.  Does this represent an unacceptably large sum of money and time to be compatible with the goal of maximising our impacts for the good?

In the light of this reality, the rationalist suggestion I have encountered – that one guard against a desire to become a parent by pre-emptively being sterilised before the desire has arisen – seems a recipe for psychological disaster.

 Finally we may ask whether parenthood – and the resulting person created – will benefit the wider world? This is a harder good to calculate or rely upon. The inheritance of specific character traits is difficult to predict. It’s certainly not guaranteed that your offspring will embrace all of your values throughout their lifetime. The burden of onerous parental expectations are extensively documented, and it would appear foolish to have children on the expectation they will be altruistic in the same way you are. However, your child is likely to resemble you in many important respects. By adulthood, the heritability of IQ is between 0.7 and 0.8,[13] and there is evidence from twin studies of significant heritability of complex traits like empathy.[14] This would give them a high probability of adding significant net good to the world.

That's rather confronting:

* a '5' on a scale of happiness ain't that bad

* don't stress too much when raising your biological kids, you can't do that much

* they're probably not worth having anyway

Just kidding. But, the evidence is quite fascinating.