[Mark,]

Fear not, Black's Law Dictionary is just a really nice way of getting a handle on the technical meaning of many legal terms (like theft, ownership and property). I actually think the definitions bear out your equation. Sure, "theft" refers us to ownership, and ownership to property (suggesting a relation of dependence rather than one of equivalence), but all three depend upon the fundamental power of one to exclude others from receiving the benefit of a thing or idea. Theft, sometimes known as "conversion," essentially involves the obstruction of benefit flowing to someone otherwise entitled to receive it. The wonderful thing about making this observation in the law is that the term really means just that. Sure, common usage might depart to a greater or lesser degree, but counsel arguing to a court must abide by this understanding of the term. So you are absolutely correct: the ONLY difference between theft and ownership is whether the possessor wins!

[Personal correspondence deleted.]

David