Surplus and Value

Surplus-Value is usually analyzed as the difference between the value of a manufactured product and the value of the raw material prior to the manufacturing process.  However, there is a more fundamental analysis, as is signified by the hyphen--differentiating the surplus in the material, i. e. how it has been modified, and the value of that surplus.  So, that Labor is the source of the modification, does not entail that it has value.  Rather, it has value only insofar as the finished product has use.  In other words, the formulation of the concept 'source of Value' is ambiguous--it might signify the cause of a valuable modification, but it might also signify the act by which Value is ascribed to something.  Thus, absent a disambiguation, the Labor Theory of Value and the Use Theory of Value are not inconsistent.  However, given the clarification, they are, and the latter seems correct.  Which does not undermine the Marxist diagnosis of Exploitation as stealing from the Labor that increases Value by the modification of the given.