Zhu Yuanzhang, the founding emperor of the Ming Dynasty, in his later years, had serious suspicion, coldness and absurd behavior, such as treating the past meritorious officials as enemies in his mind and killing more than 100,000 people indiscriminately, which led to the legendary record of “burning meritorious officials’ buildings”. These manifestations are in line with the characteristics of callousness, suspicion, irritability, and irritability of mental disorders in old age. At 2:03 p.m. on March 14, 1883, Karl Marx, the greatest thinker of our time, sat down in his easy chair and stopped thinking. Marx had spent his last year as a virtual mental cripple. He was devastated by the death of Yanni, his letters generally reveal a depression and frustration, and his scientific work could not be talked about at all, and it was at this time that he blurted out the phrase often used by all vultures later: “He himself was not a Marxist in any case. Stalin suffered from a severe mental disorder associated with cerebral arteriosclerosis. It manifested itself in emotional callousness, even to the point of brutality, so that later he did not form a family, treated his children as if they were strangers, suspected everything, and created terror and repression for no reason at all, which was frightening. The paranoia of his thinking and lack of judgment led him to miss charlatans, to search for the elixir of immortality, and to concoct the “White Shirt Conspiracy” before his death under the influence of obvious persecution delusions. Freud was an Austrian psychiatrist who spanned the 19th and 20th centuries. In his 1884 feature article “On the Coca Tree,” Freud described the effects of cocaine: “The effects of cocaine on the nerves include euphoria The effects of cocaine on the nerves include euphoria and a long-lasting euphoria that is indistinguishable from the normal euphoria that a healthy person has. He simply feels normal and happy and finds it hard to believe that he is under the domination of the drug”. This shows that Freud was an addicted cocaine user. The homicidal Adolf Hitler suffered from Parkinson’s disease, temporal lobe epilepsy, which was not recognized at the time, addiction to central nervous stimulants and personality disorders. These illnesses played a role in Hitler’s behavior to varying degrees, and were particularly evident in his bizarre behavior during his last three years in power at the end of the Third Reich. British Prime Minister Winston Churchill was Prime Minister again from 1951 to 1955 at the age of nearly 80. During this period, he had already suffered two strokes and multiple bouts of Alzheimer’s disease on top of recurring cerebrovascular insufficiency, which led to a deterioration in his leadership skills to the point where he was supported by central nervous stimulants.