Abstract expression - depicting something not having a physical or concrete existence. 

Origins of Visual Abstraction

• Calligraphy: Chinese and Islamic.
• Far East painting schools: Wang Mo (王墨) (splashed-ink);
• Chan-buddhist painting, Liang Kai (梁楷), Zen art (e.g. enso), Dajian Huineng (大鑒惠能), Sesshu Toyo;
• Tiantai buddhism: Yu Jian (mid-13th century),
• Daoist painting: Zhu Derun