The defining principle is that all human characteristics can be measured from one person and quantified. The measures gained form one person are different to those gained from another. In Baron-Cohen's study, they use the Eyes task to test TOM in individuals with autism/AS compared to without. The Eyes task was used on three groups of people: adults with autism/AS, normal adults and adults with Tourette's syndrome. From these three groups, three separate scores were collected, means of 16.3/25 for autistic/AS, 20.3 for normal, and 20.4 for TS. This links to the defining principle as the measures gained show that whether having TOM or not differ in the eyes task