Personality is generally understood in two different ways: (1) trait based and (2) situational. A trait-based understanding defines personality as the relatively stable set of psychological characteristics that influence an individual’s attitudes and behaviors and differentiate one individual from another. People have a variety of personality traits formed by their genetic predisposition and long-term learning history. A situational understanding defines personality as the sum total of ways in which an individual reacts and interacts with ­others and with his or her environment. Human behavior is a function of both psychological dispositions and the immediate situation that a person is in. The history of the study of personality traces back to 370 b.c.e., when Hippocrates proposed the “four humours,” through which he believed that individual differences ...