 Besides the definition of the appropriate language for the combined logic, another important question that immediately arises is: should the logics \({{\cal L}}_1\) and \({{\cal L}}_2\) (to be combined) be presented in the same way? In other words: is it possible to combine logics defined by different paradigms? For instance, how could one combine a logic \({{\cal L}}_1\), defined by a sequent calculus, with a logic \({{\cal L}}_2\), represented by a (Hilbert-style) axiomatic system? How should the resulting logic \({{\cal L}}\) be represented: as a sequent calculus, as an axiomatic system or as a mixed proof system? Consider now another (even worse) situation: the logic \({{\cal L}}_1\) is described by semantical means (that is, through semantic structures such as valuations or Kripke models) whereas the logic \({{\cal L}}_2\) is presented through a syntactical proof system, such as a natural deduction system, sequent calculus or a Hilbert-style axiomatization. Could the resulting (combined) logic be better presented semantically or syntactically?