When people are exhausted, they tend to develop coldness and irritability; when people are in financial difficulty, they tend to become narrow-minded and calculating; when people are happy, they are more likely to be tolerant and optimistic. Therefore, in many cases, personality is not a fixed quality of a person, but an external manifestation of the environmental state they are in. So often we need to cultivate the mind, and we also need to improve our living conditions. Circumstances determine mood, and life nourishes one's outlook.