This is meant to be a quick, silly, example heavy explaination of the non-identity problem.

The Non-identity problem, (from very intuitive assumptions), implies that bringing people into existence can't either be right or wrong (regardless of how amazing or shit their lives are). 

E.g. 1: Climate Change

If we fuck up the planet we will change who comes to exist in future generations (as, for example, people will have sex at different times) and they will obviously have shit lives. It seems messing up the planet is wrong as future generations are 'harmed' but harmed means 'worse off than they otherwise would be' but they otherwise wouldn't exist (and you don't have a welfare level for comparison if you don't exist), so they're not worse off. So either these people living shit lives aren't harmed or we have to reject this definition of harm. Both are weird. 

E.g. 2: Creating people with serious health conditions/ disabilities

For another example, is bringing into existence someone who is badly disabled, (but who lives a life that's worth living) harming them? They're living a shit life so you want to say they're harmed, but they're not worse off than they otherwise would be, as otherwise they wouldn't exist. So, by a comparative account of harm, we can't say they're harmed. 

In other words, to say bringing them into existence is wrong you have to say that you have harmed them, but to have harmed them they have to be worse off than they would be otherwise. But otherwise they wouldn't have existed (and so don't have a wellbeing level), so they're not worse off than they would have otherwise been, so bringing them into existence isn't wrong. 

This messes with Longtermism

This also fucks with ideas about benefiting people. Longtermism seems prioritise preventing extinction so humanity survives so future people live amazing lives. But someone who is born because extinction was prevented isn't better off than they otherwise would be (as they otherwise wouldn't exist), so we can't say they've been benefited by the actions of those that preserve humanity.

Basically, the non-identity problem (assuming the comparative account of harm and that harm has to be person affecting) entails that if you're action brings someone into existence, you didn't help or harm them, regardless of how good or bad their life is.

Solutions

The non-identity problem makes us either:

• Bite the bullet: accept that actions that affect who comes into existence are neither right nor wrong.
• Reject the comparative account of harm: say that someone is harmed even if they're not worse off that they would otherwise have been.
• Have a non-person affecting morality: say that actions can be right or wrong even if they don't benefit or harm anyone in particular.