Anthropologists describe feng shui as a symbolic system for reading landscapes and a social tool within lineages. In the West, it became a home decor product.
Bệnh Dược (病藥, 'disease and medicine') is a BaZi principle that finds a chart's flaw and picks the Useful God to correct it, seeking Five Elements balance.
Thủy Hỏa Ký Tế (No. 63) is the only hexagram with all six lines in correct position and paired. It teaches small success and a good start but chaotic end.