1. Appearance
- Round-faced, wide forehead, cheekbone sticking out, and has sparkle in the eyes.
- Hearing is especially developed.
- Has thick neck and big head.
- Has clear appearance and thin body. The upper body is developed but the lower body is weak.
- The upper chest is developed.
- Weak backbone and back.
- The legs are weak to have unstable posture.
- Has small hips.

2. Personality

Character
- Very outgoing, but somewhat shy.
- Has strong pride, brave and active with masculine character.
- Smart and creative.

Interpersonal relationship
- Sociable and is good at speaking.
- Forms the relationship favorable to oneself.
- Good with social relationships.

Emotional expression
- Explodes when angry.
- Is angry at others when things don’t work as preferred.
- Do as one pleases and to not regret.
- Self-righteous, has no plans and is weak on detail.
- Anger explodes when once angry.

Self-expression
- Quick in temper and has notion for heroism, and try to express oneself.

Adaptation to situation
- Adapts well to any situation.

Work performance
- Has decisiveness and spirit of a leader.
- Smart and always busy, but is rational on handling the work.

Attitude towards work
- Always in a hurry, but rational on handling the work.

Words and behaviors
- Talkative and bustling, but rational.

Behavioral form
- Always moves busily, but substantial.

3. Physical constitution and health checking method, most common illness
☞ Has good lung function, but weak liver function
- When there is problem in ruining, illness must be checked
- When hot food or food with a lot of fat is enjoyed instead of light and cold food, it may cause illness in the throat or on the stomach
- Due to weak lower body, the lower body must be trained with exercise to avoid illness.
- Frequent anger and too much sadness may result in illness on the liver and bowels.
- Big lump and amount of excrement and urine specifies the healthiness.
- White face tone shows healthiness.
- Thin skin shows healthiness.
- If there is a hard lump below the solar plexus, it is not good for the body.

Perfect healthiness
- Great amount and frequent urine specifies healthiness.
- Normally, there is no problem in urine, but there is discomfort when the body is ill.

Very serious illness
- If the constipation continues for 8~9 days and have frequent saliva or foam in the mouth, it is suspicious of serious illness, and treatment must be received quickly.

Serious illness
- Yul Gyuk Syndrome (vomiting), Ban Wi Syndrome (gastric cancer), and Hae Yeok Syndrome (lethargy) are constitutional illness of Taeyangin, and these symptoms are not shown until the illness is severe, and normally, the person looks healthy.

※ The symptoms of 3 illnesses are shown below.
- Yul Gyuk Syndrome – The symptoms are difficulty in swallowing food, and even if swallowed, it does not do down to the stomach and is vomited. There is a feeling of cool breeze on the throat, but with fever and boiling sound in the stomach. If there are symptoms of diarrhea or dysentery, it is not Yul Gyuk Syndrome.
- Ban Wi Syndrome – After eating, there is a stuck feeling in the solar plexus, and after some time, there is vomiting. The food from breakfast can be vomited at night and the dinner can be vomited in the morning. In Western medicine, it can be diagnosed as gastric cancer, gastroadynamic, and pyloric stenosis.
- Hae Yeok Syndrome – There is a severe feeling of lethargy on the entire body and even irritating to talk or move, and there is loosening feeling on the legs to lose weight. There is no paralysis, swelling or pain on the legs, or chill or fever.

Most common illnesses to Taeyangin 
Taeyangin are not well known on the pathology and pharmacology of illnesses, because the ratio of Taeyangin is the lowest among four physical constitutions. However, according to study results until today, it is known that most common illnesses of Taeyangin are illnesses on the liver and bowels, indigestion, stricture of the esophagus, chronic backache, infertility, angina, flushing, and eye disease.