《黄帝内经·素问·三部九候论》
中部之天候可以诊断肺脏之病变，中部之地候可以诊断胸中之病变，中部之人候可以诊断心脏之病变。
天以候肺，地以候胸中之气，人以候心。
The Heavenly Climate in the middle portion can diagnose lung disorders, the Earthly Climate in the middle portion can diagnose chest disorders and the Human Climate in the middle portion can diagnose heart disorders.