Do you have the maximum number of children biologically possible? If not ( and I assume you haven't ), then you've made choices that have prevented others from existing. Assuming you are okay with that ( and I assume you are ) then the decisions involved are not a simple as you portray.

>Do you have the maximum number of children biologically possible?

You can't reason about ethics from the standpoint that whatever you are doing right now is known to be ethical. If you did that, you'd just be constructing post-facto justifications for decisions you already made. There are plenty of things I should be doing from a utilitarian standpoint that I don't do (I'm not saving the maximum number of African children, for example).

> You can't reason about ethics from the standpoint that whatever you are doing right now is known to be ethical.

An excellent point...but we DO reason about ethics. We can draw parallels from our decisions in other areas to see if we are being consistent. Even if we can't achieve objectivity we can try for it and thus get closer.

And from this I find I feel bad about the good to other living creatures I COULD be doing and am not....but that I don't feel sorrow for the lack of of sorrow and joy from creatures that are merely potential.

Perhaps you feel differently. Others certainly do. I just want to point out that it's something worthy of thinking about rather than tossing out a facile "existence is always better".