From
陈子昂《
登幽州台歌》 (Tang, c. 696 CE), a 22-character masterpiece:
前不见古人,后不见来者。念天地之悠悠,独怆然而涕下 (Ahead I see no ancients; behind, no one yet to come. I ponder heaven and earth in all their vastness, alone, mournful, tears falling). Widely considered the most concentrated expression of existential loneliness in classical Chinese poetry.