Bokuseki

Bokuseki (墨跡) is a Japanese term meaning "ink trace", and refers to a form of Japanese calligraphy ("shodō") and more specifically a style of "zenga" developed by Zen monks. 
"Bokuseki" is often characterized by bold, assertive, and often abstract brush strokes meant to demonstrate the calligrapher's pure state of mind (see "Samadhi"). The aim in making "Bokuseki" is to represent ones single-moment awareness by brushing each word or passage with a single breath, ultimately realizing Zen and manifesting ones "zazen" practice into physical and artistic action. Fundamentally "bokuseki" is a reflection of one's spontaneous action (see: Buddha-nature, "katsu") free from one's superficial or rationally oriented mind.