According to psychologist E. L. Thorndike, who founded the study of social intelligence, the term should be defined as the ability "to act wisely in human relations." Thorndike felt it was implausible to this type of intelligence, as opposed to abstract intelligence or mechanical intelligence. Other psychologists, however, disagreed with this assessment.

There are several methods for testing social intelligence, including the George Washington Social Intelligence Test (GWSIT). The GWSIT, however, was deemed unable to measure social intelligence accurately because of its heavy reliance on words and expressions. As a result, the test is more appropriate for the measurement of abstract intelligence. Another test is the Vineland Social Maturity Scale, which measures social intelligence by social age, also known as mental age, and social quotient, which is intelligence as determined by social age divided by chronological age. The weakness of this test lies in the fact that it takes into account irrelevant factors, such as motor skills and linguistic skills, which cloud the measurement of social intelligence.

The difficulty in accurately deciphering social intelligence through tests is due to the many components it encompasses. One social intelligence model consists of three components: social sensitivity, the inferences one makes while socializing and the role one plays within a group; social insight, including social comprehension, psychological insight, and moral judgment; and social communications including social problem solving. Several other models and theories have been suggested as well.

In a book entitled Social Intelligence: The New Science of Human Relationships, Daniel Goleman explores the connection between our social interactions and our health. He elaborates upon a brain-to-brain link that encourages humans to connect with another. According to this theory, a good relationship might have the ability to fortify the body’s immune system, while a stressful relationship might cause digestive problems. Such a link can further clarify the mechanics involved in a teacher inspiring his students or the bond between a mother and a daughter. The importance of social intelligence does not diminish simply because it is difficult to assess.