RESUMEN
Brain diseases in traditional Chinese medicine were complex and difficult to diagnosis and treatment， and new diagnostic and therapeutic ideas are urgently needed. The onset of the disease was the result of the struggle between healthy qi and pathogenic qi. Common types of the onset of diseases included sudden onset， slow onset， latent onset， secondary onset， and recurrent onset， reflecting the strength of the healthy qi and pathogenic qi， the pathogenic qi that reduced diseases， the site of onset， and other informatin. “Identificating the onset of diseases” was simple and easy to operate， and helped to clarify the complex development of encephalopathy. When applying it， we should first identify urgency and importance， focus on the characteristics； grasp the tendency of diseases， and know the overall situation of the disease； compare similarities and differences horizontally； and carefully observe and dynamically understand the disease. “Identificating the onset of diseases” has the characteristics of comprehensiveness and prognosis， and can lay the foundation for pattern identification and treatment and “treating disease before its onset”.