  The strong interaction between electrons reveals the duality of the
itinerancy and the localization of quasiparticles. The physical phenomena
corresponding to each component of the duality could be realized and coexist
within the category of the uncertainty principle of the carrier dynamics, which
can be a strong reason of the complexity appearing in the strongly correlated
system. A possible mechanism for the high-temperature superconductivity is
proposed on the basis of the interplay between the renormalized expectation
quantities of both parts.
