1. For an office, the five elements of desk and chair belong to Yang, while the bookshelf for books and materials is static, and the five elements belong to Yin. Therefore, bookshelf placement should also obey the principle of balance between yin and yang, that is, bookshelf placement should correspond to desk placement.
2. In addition, in Feng Shui, the saying that "the desk is lucky and the bookcase is fierce" means that the desk should be placed in the auspicious position, while the bookshelf is just the opposite. It can be placed in the unlucky feng shui position in the office to suppress the evil spirit in the office.