The various activities during my stay in Kyoto (January-May), which include the copy-editing process and the Index-preparation for Language Faculty Science, as well as lectures at various places and discussions with various people, even including an astrophysicist of Tokyo University, made me realize (more) clearly (than before) what (outstanding) (substantive and expositional) shortcomings there are in the book.

That, of course, is a good thing.

Due to the timing of the production of the book, however I cannot incorporate the possible innovations in the forthcoming book.

But, they will be incorporated in future works.