 That neo-Confucianism included comprehensive philosophical systems that had incorporated ideas and practices from Buddhism and Daoism, relegating them into subordinate places within its own philosophy. The Confucianism in Japan that was a legacy from the ancient period barely touched on metaphysical, epistemological, and psychological issues and had hardly mentioned themes related to nature, art, and creativity. Hence, up to the Edo period, Japanese philosophers had turned to Buddhism to address those themes. Indeed, from the time of Kūkai, Buddhism had relegated Japanese Confucian thought to being not much more than a social philosophy. The newly imported neo-Confucianism, however, had assimilated enough Buddhist and Daoist ideas that it could address a full complement of philosophical problems in a single comprehensive system. When the second hegemon, Toyotomi Hideyoshi, brought prisoners of war to Japan from his failed attempt to conquer Korea in the late sixteenth century, included in the group were some Korean officials who were also scholars of Chinese neo-Confucianism. Rinzai Zen monks became disciples and soon Japan had its own emergent schools of neo-Confucianism, a phenomenon the Tokugawa shogunate would welcome.