Literature Reference: 'Lin' from 'The Book of Songs - The Toes of the Lin': 'The toes of the Lin, the noble son.' 'Yu' from 'The Book of Changes - Xi Ci I': 'Heaven is high and earth is low; thus the positions of Qian and Kun are fixed. High and low are arrayed, and thus the positions of the noble and the humble are settled. Movement and stillness have their norms, and thus the distinctions of the strong and the soft are determined. Things of a kind gather together, and things of a group separate; thus fortune and misfortune are born. In heaven they form images, and on earth they take shape; thus change and transformation are visible. Therefore, the strong and the soft rub against each other, and the eight trigrams stimulate each other; they are stirred by thunder and lightning, moistened by wind and rain; the sun and moon move, bringing cold and heat.'