"Cold Food Observance," or Han Shi Tie, by Su Shi (苏轼), is a celebrated example of Running Script (xingshu) from the Song Dynasty. It's not just a simple piece of calligraphy; it is an emotional outpouring that was created in a period of difficulty and exile for Su Shi. The work captures a range of emotions, including grief, frustration, and a longing for home. Its masterful use of brushstrokes and its profound emotional depth have made it one of the most cherished works in the history of Chinese calligraphy.