Which symptom is indicative of an external pathogenic invasion?

Body aches and chills are classic symptoms that suggest an invasion by an external pathogenic factor, such as wind, cold, or dampness. In Traditional Chinese Medicine (TCM), when the body is invaded by such external pathogens, it can lead to a disruption of the body’s normal functions. The presence of chills indicates that the body is responding to an external threat, while body aches often represent a manifestation of the body's defensive response trying to fight off the invading pathogen.

This combination is characteristic of the body's reaction to an acute illness, particularly when it is linked to climate factors. Persistent fatigue, constipation, and heat sensations in the stomach tend to indicate internal imbalances or issues, rather than an immediate external invasion. For instance, persistent fatigue is more closely aligned with deficiency syndromes, while constipation may point to a deficiency of Qi or Yin. Heat sensations in the stomach usually reflect internal heat conditions. Therefore, the symptoms of body aches and chills directly align with the idea of an external pathogenic invasion, making it a clear indicator in the context of TCM diagnostic theories.