We investigate the dualisability problem for finite relational structures and highlight differences with the more familiar dualisability prob-lem for finite algebras. For example, while many inherently non-dualisable algebras are known, we shall show that there are no inherently non-dualisable relational structures at all. We will also prove that, for every finite set with at least four elements, there are uncountably many non-equivalent relational structures on that set that are all dualised by a fixed alter ego.
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