This volume is about "Structure." The search for "structure," always the pursuit of sciences within their specific areas and perspectives, is witnessing these days a dra matic revolution. The coexistence and interaction of so many structures (atoms, hu mans, cosmos and all that there is in between) would be unconceivable according to many experts, if there were not, behind it all, some gen eral organizational principle. s that (at least in some asymptotic way) make possible so many equilibria among species and natural objects, fan tastically tuned to an extremely high degree of precision. The...