The "frog effect" originated in the late 19th century. Cornell University in the United States once conducted a famous "frog experiment": they put a frog in a boiling cauldron, and the frog jumped out immediately with an electric shock. Later, people put it in a big pot full of cold water and let it swim freely. Then slowly heat it with a small fire. Although the frog could feel the change of the outside temperature, it did not jump out immediately because of inertia, until the heat was unbearable and it lost its ability to escape and was cooked. After analysis, scientists believe that the frog was able to "escape from danger" for the first time because it was violently stimulated by boiling water, so it jumped out with all its strength. The second time, because it didn't feel the stimulation obviously, the frog lost its vigilance and crisis consciousness. It felt that the temperature was just right, but when it felt the crisis, it was unable to escape from the water.