"A corporation sole is one consisting of one person only, and his successors in some particular station, who are incorporated by law in order to give them some legal capacities and advantages, particularly that of perpetuity, which in their natural persons they could not have had. In this sense, the sovereign in England is a sole corporation, so is a bishop, so are some deans distinct from their several chapters, and so is every parson and vicar." --Black's Law Dictionary, Sixth Edition, Page 341 [Aggregate and Sole]