  Both algebraic and computational approaches for dealing with similarity
spaces are well known in generalized rough set theory. However, these studies
may be said to have been confined to particular perspectives of
distinguishability in the context. In this research, the essence of an
algebraic semantics that can deal with all possible concepts of
distinguishability over similarity spaces is progressed. Key to this is the
addition of choice-related operations to the semantics that have connections
with modal logics as well. Among these we focus on a semantics that is based on
local clear distinguishability over similarity spaces.
