Patient**, male, 20 years old, is a new recruit. He has been in the army for several months, and the army reflected that the patient could not keep up with the pace of the army, was very slow in doing things, ranked last in every training project, had poor interactions with others, sometimes laughed at himself, and suspected that there was something wrong with his intelligence. He graduated from vocational school. The examination found that the patient’s expression was bland, admitted that he could not keep up with the army life, and said that he “laughed only when he thought of something funny”. He could not even say his home address. The IQ score was 76, which was considered as “borderline intelligence”. One year later, Liu Yan, a psychiatrist at the Shanghai Mental Health Center, brought the patient’s family back to the hospital, saying that the patient was very dull after returning home, and that the local hospital had recommended a visit to Beijing, where a hospital had diagnosed “schizophrenia” and was only now getting better after treatment, asking about the diagnosis. On re-examination, the patient was more cooperative, his intelligence was acceptable on rough tests, and he knew his home address, simple addition and subtraction, and idioms. After deeper understanding, the patient said that he heard neighbors talking during vocational school and thought someone was stalking him, worrying that others would harm him, and that the thoughts in his head were known to others without saying anything. After that, he saw a doctor in the company of his family, and then all these feelings disappeared. Vocational school is also considered to have graduated with poor grades, generally 30 or 40 points. Consider the diagnosis, or schizophrenia. There are several points worth noting in this case: 1. It is quite important for the family to provide an accurate and detailed medical history. This case is unique because it is a new recruit and the army does not know the patient’s growth and development, and for various reasons, it is not possible to provide a medical history of the vocational school that year; 2. A detailed psychiatric examination is very important. In this case, hallucinations and delusions were not detected during the first examination for various reasons, but some previous abnormal sensations were acknowledged in later examinations; therefore, the diagnosis of mental illness sometimes requires repeated examinations; 3. Patients with schizophrenia have impairment of cognitive function, which can be caused by the disease itself and partly by drugs. Some patients with mental retardation also develop symptoms of schizophrenia while growing up, and the previous diagnosis of “grafted mental disorder” is now diagnosed together with the two disorders.