> What I'm saying is that "world in crisis" is not a good reason for you to reduce the number of children you plan to have, if your personal preference is in fact to continue living in this "world in crisis" yourself.

I would suggest you have a poor grasp of the timescale of the "world in crisis" then.

The AGW threat, as put forward in the Intergovernmental Panel on Climate Change (IPCC) reports is a slow boiling frog scenario, one that steadily gets worse as insulation in the atmosphere continues to increase.

A number of people may, and indeed do, consider that their lives from this time until their projected death assuming good health, will be pleasant enough, but that the lives of their children and potential grandchildren will be worse and might face a rapid decline in quality of life at some point.

Another group, with some overlap in the greater Venn diagram, might consider that one part of a solution includes decreasing overall consumption - and a reduction of numbers in high per capita consumption societies makes sense.

The reasoning of both groups is simple enough, little is achieved by killing themselves, something is gained by a reduction in human population, and hypothetic non existing grand children are spared a life much worse.

For most people, though, there's not neccesarily any clear decision, just behaviour that follows observations made decades past by Hans Rosling and others; as education and quality of life improve, so fall birth rates.