disloyalty and to establish rewards and punishments." Similarly, the feudal lord Takeda Nobushige (1525–1561) stated: "In matters both great and small, one should not turn his back on his master's commands ... One should not ask for gifts or enfiefments from the master ... No matter how unreasonably the master may treat a man, he should not feel disgruntled ... An underling does not pass judgments on a superior." Nobushige's brother Takeda Shingen (1521–1573) also made similar observations: "One who was born in the house of a warrior, regardless of his rank or class, first acquaints himself with a man of military feats and achievements in loyalty ... Everyone knows that if a man doesn't hold filial piety toward his own parents he would also neglect his duties toward his lord. Such a neglect means a disloyalty toward humanity. Therefore such a man doesn't deserve to be called 'samurai'." The feudal lord Asakura Yoshikage (1428–1481) wrote: "In the fief of the Asakura, one should not determine hereditary chief retainers. A man should be assigned according to his ability and loyalty." Asakura also observed that the successes of his father were obtained by the kind treatment of the warriors and common people living in domain. By his civility, "all were willing to sacrifice their lives for him and become his allies." Katō Kiyomasa was one of the most powerful and well-known lords of the Sengoku period. He commanded most of Japan's major clans during the invasion of Korea. In a handbook he addressed to "all samurai, regardless of rank", he told his followers that a warrior's only duty in life was to "grasp the long and the short swords and to die". He also ordered his followers to put forth great effort in studying the military classics, especially those related to loyalty and filial piety. He is best known for his quote: "If a man does not investigate into the matter of Bushido daily, it will be difficult for him to die a brave and manly death. Thus it is essential to engrave this business of the warrior into one's mind well." Nabeshima Naoshige (1538–1618 AD) was another Sengoku daimyō who fought alongside Kato Kiyomasa in Korea. He stated that it was shameful for any man to have not risked his life at least once in the line of duty, regardless of his rank. Nabeshima's sayings were passed down to his