People are abstract.

Ten is a number. You cannot touch it, you cannot feel it, you are unable to measure it. If fact, I could have written "10" as "A₁₆" or "1010₂" or "12₈". It is all the same, they all have the same meaning. And yet, with all of this meaning, you cannot actually, in our reality, do anything with ten.

A person is the same way. You embody a physical shell, a collection of cells, atom and molecules, that you call you. But you, the essence, the consciousness is not the collection of biology. Your body is merely a something that you resides in. A nice squishy home if you will.

By that reasoning, it stands that you are able to move in and out of these shell containers at will, however, try as you may, you are not able to leave you body, and go roost in another location. A person seems to be permanently stuck inside their body, from birth, to unfortunate death.

Why is this? Why am I, or you, able to simply wish I was in a different body? Why isn't it as easy for me to express myself as a green ogre as it is to express ten as 10 or A?

It all has to do with complexity. Ten is such a small item, you are able to fit it anywhere, on a sheet of notebook paper or on a bathroom stall. But look at a person, their complexities, their intricacies, the shallowness and their depth. It takes an organ with as many connections as their are stars to simply house such a complex entity, and an entire organism containing trillions of cells to power and maintain it.

So, in order to have to ability to transfer such a complex entity, one must have a suitable complex system that has the capability to contain it. And what do we, as humans, have that is currently complex enough to do such a thing?

Nothing as of now.