First, it is used to resolve hostility. Hanging a mirror on the window is one of the means to ward off evil spirits in Feng Shui, because in Feng Shui, the mirror can reflect evil spirits, and the Feng Shui function of turning evil spirits into evil spirits is mainly used to drive evil spirits out of the room.
Second, resolve sharp corners. For example, there is a sharp corner facing our house outside, which forms sharp corners, such as good and evil, right and wrong, injury, lotus and so on. According to the principle of geomantic omen, we only need to install a mirror facing this sharp corner, and use the sharp corner image in the mirror to balance the suffocation of the outdoor sharp corner against our house, so as to resolve the sharp corner evil.