'The Lord of the Rings and Philosophy'

[Kuruharan]

the phantom

What would I do? Well, I suppose it would mostly depend on who was hanging over the cliff.

That is part of the problem though. The question assumes that you do not know this person and don't know anything about them. There is also no time to launch a full scale inquiry into the matter because the victim's arms are getting mighty weak. And even if you did, you have no way of checking what the victim tells you before they fall. If they are a bad sort they are probably not going to tell you that.

It is essentially a question of whether you consider another life to be at least as valuable as your own (however much value you place on your own life).