Most actions and possessions are measured by cost, whether it is work, money or usefulness. We as a species as accustomed to sorting everything by the value of practicality, entertainment, and such standards. We can make proportionalities for theft and destruction of property. Murder is another category altogether.
While we love this system for being so predictable and simple, it can't explain everything. In this case, what is the price of losing a soul? The consciousness rather than the body is usually presumed to be the part that makes us human. But the soul can't do work, be observed, or even be proved to exist without a host. It cannot be sold, bought, or collected.
Our physical being cannot be weighed either. The purpose is not consumption, so it cannot be placed by nutrition or quality.
Labor is calculated by wages. Wages aren't certain or in a constant relationship with work. And it is impossible to establish what the dead person would have done in work if they had met a different fate.
Most other perspectives of human worth are too objective and not logically meaningful. A life for a life doesn't apply properly to intricate determinations of worth. And if the killer took several lives, it may not be possible to even the conditions accordingly.
With no answer in sight, what determines the value? What punishment or reimbursement is morally mandated for the party at fault? Should humanity cease to seek an equal exhange?
In my opinion, it is a hard topic to answer concisely and definitively. I believe retribution should happen to an extent, although actions against the accused are sometimes unfair.
