Shattered Kingdoms

In the empire, to try to mug someone > try to kill them.

Attempted murder is severed limb and confiscation.
Attempted mugging is death.

Its how it has been for a long time. You want to take something from someone, take his life first. If you don't have the guts to do that, go home and weep until you do.

I have always thought of it as the Empire rewarding the act of strength and power and punishing harshly the act of weakness and cowardice.

That's pretty much the idea. The empire is a dark-aligned place and their laws reflect their twisted version of morality. It's SHOULD be mentally jarring to people raised in a relatively just and free society.

If that's the idea shouldn't ATTEMPTED murder have harsher crimes than murder itself? If your going to punish the weak and praise the strong and all...

Shouldn't the North have even less laws then? =/

No, the North survives and thrives on as much oppression as it can. It's not about rewarding strength, it's about forcing rigors and rote on people so they can survive in an environment not conducive to growing food, lacking in quite a few "natural resources", and happens to be cold enough so that quite a few children (and in some cases adults) don't survive the harsh winters.

Then they should sit in jail without limbs bleeding to death.

Not really. A jail is shelter from the elements. Some people who have no homes COMMIT crimes so they can have a place to sleep, and be fed and clothed. It's a waste of space, resources and utilities to keep a prisoner for reasons of spite and vengeance, when instead you can shelter someone else from the elements who hasn't done anything except go about their business.