{ 1 } - is nonsensical (since it makes claims that are neither empirical nor analytic) and thus should be avoided.
{ 2 } - gives us knowledge of the world that transcends sense experience.
{ 3 } - is about what ultimately exists in the world.

Russell does metaphysics by asking what kind of language structures we need to describe the world completely. For example, do we need to talk about material objects (as independent objects) -- or can we describe the world completely by just talking about our sensations?

On this view, metaphysics and science are both, in a wide sense, "empirical." The difference is that metaphysics is more speculative and tries to get at what ultimately exists in the world.