The development of the Character Strengths and Virtues (CSV) handbook (2004) represented the first attempt by Seligman and Peterson to identify and classify positive psychological traits of human beings. Much like the Diagnostic and Statistical Manual of Mental Disorders (DSM) of general psychology, the CSV provided a theoretical framework to assist in understanding strengths and virtues and for developing practical applications for positive psychology. This manual identified 6 classes of virtues (i.e., "core virtues"), underlying 24 measurable character strengths.
The CSV suggested these 6 virtues have a historical basis in the vast majority of cultures; in addition, these virtues and strengths can lead to increased happiness when built upon. Notwithstanding numerous cautions and caveats, this suggestion of universality hints threefold: 1. The study of positive human qualities broadens the scope of psychological research to include mental wellness, 2. the leaders of the positive psychology movement are challenging moral relativism, suggesting people are "evolutionarily predisposed" toward certain virtues, and 3. virtue has a biological basis.
The organization of the 6 virtues and 24 strengths is as follows:
Recent research challenged the need for 6 virtues. Instead, researchers suggested the 24 strengths are more accurately grouped into just 3 or 4 categories: Intellectual Strengths, Interpersonal Strengths, and Temperance Strengths or alternatively, Interpersonal Strengths, Fortitude, Vitality, and Cautiousness These strengths, and their classifications, have emerged independently elsewhere in literature on values. Paul Thagard described examples; these included Jeff Shrager's workshops to discover the habits of highly creative people. Some research indicates that well-being effects that appear to be due to spirituality are actually better described as due to virtue.