We began by determining what, specifically, a genetic trait should measure, and for practical purposes, we evolved. Evolution is a gradual process in which something changes into a different and usually more complex or better form. Refined this definition had a pool of experts critique and generate definitions for each individual characteristic of people we wanted to measure. Mental disorders like: schizophrenia, depression, and bipolar appear to measure the average persons character with some mental correspondence to each mental state.
Mental disorders can be fatal to tens of millions of people each year; undiagnosed disorders can be difficult to deal with, but equally positive, because certain characteristics found in disorders may provide deeper insight than normal, help individuals think intensely about problems, and cause creativity, energy, and productivity.